AU2024257566A1

AU2024257566A1 - Hot-dip plated steel material

Info

Publication number: AU2024257566A1
Application number: AU2024257566A
Authority: AU
Inventors: Shinya Furukawa; Yasuto Goto; Kohei Tokuda
Original assignee: Nippon Steel Corp
Current assignee: Nippon Steel Corp
Priority date: 2023-04-17
Filing date: 2024-03-14
Publication date: 2025-10-16
Also published as: EP4700151A4; KR20250165368A; WO2024219123A1; CN121002225A; TW202442889A; EP4700151A1; JPWO2024219123A1

Description

layer has a sacrificial corrosion protection action, no significant problems occur in terms 1 to greater progression of corrosion thereafter. In general, since the Zn-based plated

DESCRIPTION increases, and the corroded area then acts as a starting point for further corrosion, leading

TITLE OF INVENTION: HOT-DIP PLATED STEEL MATERIAL appearance. In addition, once corrosion has occurred, the surface area of corrosion

layer as much as possible because white rust is likely to deteriorate the external

a corrosion product. It is preferable to prevent generation of white rust in the plated

TECHNICAL FIELD layer is corroded, the Zn-based plated layer reacts with oxygen in the atmosphere to form

5includes

[0001] minimization of the amount of white rust formed. When a Zn-based plated

The present invention relates to a hot-dip plated steel material. An important issue from the viewpoint of corrosion resistance of a plated layer

[0003]

Priority is claimed on Japanese Patent Application No. 2023-067061, filed April means for inexpensive antirust of steel materials.

17, 2023, the content of which is incorporated herein by reference. required, such as the fields of civil engineering, construction, and automobiles, as a

BACKGROUND ART dip Zn plating method is used in various fields where antirust for steel materials is

to apply some kind of antirust treatment to resist corrosion of the steel material. A hot-

10 [0002] In a case where a steel material is used for a long period of time, it is preferable

[0002] In a case where a steel material is used for a long period of time, it is preferable BACKGROUND ART to apply some kind of antirust treatment to resist corrosion of the steel material. A hot- 17, 2023, the content of which is incorporated herein by reference.

dip Zn plating method is used in various fields where antirust for steel materials is Priority is claimed on Japanese Patent Application No. 2023-067061, filed April

required, The present such asrelates invention the fields of plated to a hot-dip civil steel engineering, material. construction, and automobiles, as a

15[0001] means for inexpensive antirust of steel materials. TECHNICAL FIELD

[0003]

An important issue from the viewpoint of corrosion resistance of a plated layer TITLE OF INVENTION: HOT-DIP PLATED STEEL MATERIAL

DESCRIPTION includes minimization of the amount of white rust formed. When a Zn-based plated 1

layer is corroded, the Zn-based plated layer reacts with oxygen in the atmosphere to form

20 a corrosion product. It is preferable to prevent generation of white rust in the plated

appearance. In addition, once corrosion has occurred, the surface area of corrosion

increases, and the corroded area then acts as a starting point for further corrosion, leading

to greater progression of corrosion thereafter. In general, since the Zn-based plated

25 layer has a sacrificial corrosion protection action, no significant problems occur in terms

Patent Document 1: PCT International Publication No. WO 2019/230894 2

[0006]

of material performance even though defects reaching the base metal and the like or Patent Documents

corrosion of the plated layer occurs to some extent; however, a problem of deterioration Citation List

of external appearance due to white rust has been confirmed as described above. an element to the plated layer or actively forming a corrosion product.

resistance by microstructural control, and further improve corrosion resistance by adding

[0004] which these Zn-Al-Mg-based plated layers improve designability and corrosion

5used as highly corrosion-resistant On the other hand, plating with in recent respect years. toissuch A technique a Zn-based disclosed in plated layer, a plated layer

containing an element such as Sn, Ni, or Cr, which has a higher ionization tendency than For example, Patent Documents 1 and 2 describe Zn-Al-Mg-based plated layers

[0005]

Fe, is called a barrier-type coating, and does not have a sacrificial corrosion protection Zn-based plated layer.

action on Fe, easily leading to fatal material defects when defects or the like occur. appearance by adjusting the ionization tendency to approach the potential of Fe even in a

However, in such a barrier-type coating, metallic gloss can be maintained for a long possible to reduce the amount of white rust formed and improve the external corrosion

with minimal signs of use can be maintained. Therefore, it is considered that it is

10 period of time in terms of external appearance, and this metallic gloss is maintained even for a certain period of time after manufacture, so that a high-quality external appearance

for a certain period of time after manufacture, so that a high-quality external appearance period of time in terms of external appearance, and this metallic gloss is maintained even

with minimal signs of use can be maintained. Therefore, it is considered that it is However, in such a barrier-type coating, metallic gloss can be maintained for a long

action on Fe, easily leading to fatal material defects when defects or the like occur.

possible to reduce the amount of white rust formed and improve the external corrosion Fe, is called a barrier-type coating, and does not have a sacrificial corrosion protection

appearance by adjusting the ionization tendency to approach the potential of Fe even in a containing an element such as Sn, Ni, or Cr, which has a higher ionization tendency than

15 Zn-based plated layer. On the other hand, with respect to such a Zn-based plated layer, a plated layer

[0004]

[0005] of external appearance due to white rust has been confirmed as described above.

For example, Patent Documents 1 and 2 describe Zn-Al-Mg-based plated layers corrosion of the plated layer occurs to some extent; however, a problem of deterioration

used as highly corrosion-resistant plating in recent years. A technique is disclosed in of material performance even though defects reaching the base metal and the like or

2

which these Zn-Al-Mg-based plated layers improve designability and corrosion

20 resistance by microstructural control, and further improve corrosion resistance by adding

an element to the plated layer or actively forming a corrosion product.

Citation List

Patent Documents

[0006]

25 Patent Document 1: PCT International Publication No. WO 2019/230894

0.01% or more and 2.0% or less of Si, and 3 4.0% or more and 15.0% or less of Mg,

Patent Document 2: PCT International Publication No. WO 2018/139619 more than 10.0% and less than 45.0% of Al,

SUMMARY the plated layerOF has INVENTION a chemical composition including, in terms of mass%,

Technical Problem disposed on a surface of the steel material, in which

invention is a hot-dip plated steel material including: a steel material; and a plated layer

[0007]

[1] A hot-dip plated steel material according to one aspect of the present

5adopt the followingHowever, in the Zn-Al-Mg-based plated layers in the related art as described in configurations.

Patent Documents 1 and 2, the method for adding an element to the plated layer finally In order to solve the above-described problem, aspects of the present invention

[0009]

manufactured and the way of controlling the ionization tendency thereof have not been Solution to Problem

sufficiently studied, and are insufficient from the viewpoint of improving the external corrosion.

appearance and suppressing the corrosion initiation by minimizing white rust generated plated steel material capable of minimizing white rust generated at the initial stage of

An object of an embodiment of the present invention is to provide a hot-dip

10 at the initial stage of corrosion.

[0008]

[0008] at the initial stage of corrosion.

An object of an embodiment of the present invention is to provide a hot-dip appearance and suppressing the corrosion initiation by minimizing white rust generated

sufficiently studied, and are insufficient from the viewpoint of improving the external

plated steel material capable of minimizing white rust generated at the initial stage of manufactured and the way of controlling the ionization tendency thereof have not been

corrosion. Patent Documents 1 and 2, the method for adding an element to the plated layer finally

15 Solution to Problem However, in the Zn-Al-Mg-based plated layers in the related art as described in

[0007]

[0009] Technical Problem

In order to SUMMARY OF INVENTION solve the above-described problem, aspects of the present invention

adopt the following configurations. Patent Document 2: PCT International Publication No. WO 2018/139619

3

[1] A hot-dip plated steel material according to one aspect of the present

20 invention is a hot-dip plated steel material including: a steel material; and a plated layer

disposed on a surface of the steel material, in which

the plated layer has a chemical composition including, in terms of mass%,

more than 10.0% and less than 45.0% of Al,

4.0% or more and 15.0% or less of Mg,

25 0.01% or more and 2.0% or less of Si, and

0% or more and 0.25% or less of Zr, 4 0% or more and 0.25% or less of Mn,

at least one of 0.03% or more and 5.0% or less of Cu, or 0.03% or more and 0% or more and 0.25% or less of Nb,

6.0% 0% or or less more and of Ag, 0.25% or and less of V,

further including 0% or more and 0.25% or less of Co,

0% or more and 0.25% or less of Ti,

0% or more and 0.7% or less of Sn, 0% or more and 0.5% or less of P,

5 0% or more and 0.3% or less of Bi, 0% or more and 0.5% or less of B,

0% or more and 0.3% or less of In, 0% or more and 0.25% or less of Pb,

0% or more and 0.25% or less of Sb,

0% or more and 0.6% or less of Ca, 0% or more and 0.3% or less of Mo,

0% or more and 0.3% or less of Y, 0% or more and 0.5% or less of Cr,

0% or more and 0.3% or less of La, 0% or more and 1.0% or less of Ni,

0% or more and 0.3% or less of Li,

10 0% or more and 0.3% or less of Ce, 0% or more and 0.3% or less of Sr,

0% or more and 0.3% or less of Sr, 0% or more and 0.3% or less of Ce,

0% or more and 0.3% or less of Li, 0% or more and 0.3% or less of La,

0% or more and 0.3% or less of Y,

0% or more and 1.0% or less of Ni, 0% or more and 0.6% or less of Ca,

0% or more and 0.5% or less of Cr, 0% or more and 0.3% or less of In,

15 0% or more and 0.3% or less of Mo, 0% or more and 0.3% or less of Bi,

0% or more and 0.7% or less of Sn,

0% or more and 0.25% or less of Sb, further including

0% or more and 0.25% or less of Pb, 6.0% or less of Ag, and

0% or more and 0.5% or less of B, at least one of 0.03% or more and 5.0% or less of Cu, or 0.03% or more and

4

0% or more and 0.5% or less of P,

20 0% or more and 0.25% or less of Ti,

0% or more and 0.25% or less of Co,

0% or more and 0.25% or less of V,

0% or more and 0.25% or less of Nb,

0% or more and 0.25% or less of Mn,

25 0% or more and 0.25% or less of Zr,

Advantageous Effects of Invention 5 section along the thickness direction of the plated layer.

0% or more and 0.25% or less of W, contained as intermetallic compound particles within a range of 10000 µm² in a cross

0% or more and 5.0% or less of Fe, and Al) - (Cu + Ag) compounds having an average grain size of 1 µm or more may be

a remainder of Zn and impurities, and

[3] In the hot-dip plated steel material according to [1] or [2], 10 or more (Zn +

analysis value (at%) obtained by energy dispersive X-ray spectrometry in the ß phase.

a total amount of Cu and Ag satisfying 0.03% or more and 6.0% or less, and where, each of [Al], [Zn], [Cu], and [Ag] in Expression (4) is a quantitative

5 0.85 in a case where, in1.15 an (4)

[Al]/([Zn] + [Cu] + [Ag]) elemental distribution profile obtained by quantitative

analysis using a glow discharge optical emission spectrometry in a direction from a layer, and concentrations of Al, Zn, Cu, and Ag in the ß phase may satisfy Expression (4),

phase may be 3% or more in a cross section along a thickness direction of the plated

surface of the plated layer toward the steel material, a thickness of the plated layer is

[2] In the hot-dip plated steel material according to [1], an area fraction of a ß

denoted by t, and CAZ 0.1000 (3).a ratio of the total amount of Cu and Ag to a concentration of Zn in an

0.0005 CAZ (2) internal region between a 1/3t position and a 2/3t position from the surface of the plated CAZmax/CAZmin 1.20 (1) 10 layer is denoted by CAZ, an absolute maximum value CAZmax of the CAZ and an absolute minimum value CAZ of the CAZ satisfy Expressions (1) to (3),

absolute minimum value CAZ of the CAZ satisfy Expressions (1) to (3), min value CAZ of the CAZ and an layer is denoted by CAZ, an absolute maximum

CAZmax/CAZmin ≤ 1.20 ... (1) internal region between a 1/3t position and a 2/3t position from the surface of the plated

denoted by t, and a ratio of the total amount of Cu and Ag to a concentration of Zn in an

0.0005 ≤ CAZmin ... (2) surface of the plated layer toward the steel material, a thickness of the plated layer is

CAZ max analysis using a glow discharge ≤ 0.1000 ... (3). optical emission spectrometry in a direction from a

15 [2] In the hot-dip plated steel material according to [1], an area fraction of a β in a case where, in an elemental distribution profile obtained by quantitative

a total amount of Cu and Ag satisfying 0.03% or more and 6.0% or less, and

phase may be 3% or more in a cross section along a thickness direction of the plated a remainder of Zn and impurities, and

layer, 0% or and concentrations more and of and 5.0% or less of Fe, Al, Zn, Cu, and Ag in the β phase may satisfy Expression (4),

0.85 ≤ [Al]/([Zn] + [Cu] + [Ag]) ≤ 1.15 ... (4) 0% or more and 0.25% or less of W,

5

where, each of [Al], [Zn], [Cu], and [Ag] in Expression (4) is a quantitative

20 analysis value (at%) obtained by energy dispersive X-ray spectrometry in the β phase.

Al) - (Cu + Ag) compounds having an average grain size of 1 μm or more may be

contained as intermetallic compound particles within a range of 10000 μm2 in a cross

section along the thickness direction of the plated layer.

25 Advantageous Effects of Invention sacrificial corrosion protection action on a steel material. Therefore, during the 6 property that the plated layer itself is hardly corroded. A Zn-based plated layer has a

[0010] The "corrosion resistance" described in the present specification indicates a

[0013] According to the embodiment of the present invention, it is possible to provide

the hot-dip plated steel material capable of minimizing white rust generated at the initial numerical values as the lower limit or the upper limit.

numerical values described before and after "to" means a range not including these

stage of corrosion. Note that a numerical range in which "more than" or "less than" is attached to the

5numericalBRIEF DESCRIPTION values described OFasDRAWING before and after "to" the lower limit and the upper limit.

[0011] In addition, a numerical range represented by "to" means a range including the

specified.

[FIG. 1] A diagram representing a result of GDS analysis performed on a plated element in a chemical composition of a plated layer means "mass%" unless otherwise

layer of ainhot-dip Note that, the presentplated steelthematerial specification, according "%" indication toofan of the amount eachembodiment of the present

invention, and a graph illustrating an example of an elemental distribution profile. present invention will be described.

Hereinafter, a hot-dip plated steel material according to one embodiment of the

10 DESCRIPTION OF EMBODIMENTS

[0012]

[0012] OF EMBODIMENTS DESCRIPTION

Hereinafter, a hot-dip plated steel material according to one embodiment of the invention, and a graph illustrating an example of an elemental distribution profile.

layer of a hot-dip plated steel material according to an embodiment of the present

present invention will be described.

[FIG. 1] A diagram representing a result of GDS analysis performed on a plated

[0011] Note that, in the present specification, the “%” indication of the amount of each BRIEF DESCRIPTION OF DRAWING 15 element in a chemical composition of a plated layer means “mass%” unless otherwise

stage of corrosion.

specified. the hot-dip plated steel material capable of minimizing white rust generated at the initial

In addition, a numerical range represented by “to” means a range including the According to the embodiment of the present invention, it is possible to provide

[0010] numerical values described before and after “to” as the lower limit and the upper limit. 6

Note that a numerical range in which “more than” or “less than” is attached to the

20 numerical values described before and after “to” means a range not including these

numerical values as the lower limit or the upper limit.

[0013]

The “corrosion resistance” described in the present specification indicates a

property that the plated layer itself is hardly corroded. A Zn-based plated layer has a

25 sacrificial corrosion protection action on a steel material. Therefore, during the aqueous solution). The ß phase is distributed throughout the plated layer, and it is 7 The corrosion potential of the MgZn phase was (-1.1 V vs. Ag/AgCl in 1M NaCl corrosion process of a plated steel sheet, the plated layer corrodes and turns into white corrosion proceeds from the Zn-Al (ß) phase, the MgZn phase is subsequently corroded.

rust before the Furthermore, steel it was material observed that, incorrodes, and after the Zn-Al-Mg-based the plated plated layer, afterlayer turns into white rust and

[0016] disappears, the steel material corrodes, resulting in the formation of red rust. layer.

The “sacrificial corrosion resistance” described in the present specification corrosion potential (-1.3 V vs. Ag/AgCl in 1M NaCl aqueous solution) in the plated

5found that indicates a property this is because ofphase the Zn-Al (ß) inhibiting corrosion exhibits the of the electrochemically steel material at a portion where the lowest

steel material is exposed (for example, a cut end surface portion of the plated steel layer proceeded from the Zn-Al (ß) phase. Furthermore, the present inventors have

investigated. As a result, it was found that corrosion of the Zn-Al-Mg-based plated

material and a portion where the steel material is exposed due to cracking of the hot-dip First, the corrosion morphology of the Zn-Al-Mg-based plated layer was

[0015] plating layer during processing).

[0014] stage of corrosion in a Zn-Al-Mg-based plated steel material.

intensively studied the means for minimizing the formation of white rust at the initial

10 First, the results of studies on means for minimizing the formation of white rust by the present inventors will be described. Specifically, the present inventors have

byFirst, the the present inventors results of willforbe studies on means described. minimizing Specifically, the formation of white rust the present inventors have

[0014] intensively studied the means for minimizing the formation of white rust at the initial plating layer during processing).

stage of corrosion in a Zn-Al-Mg-based plated steel material. material and a portion where the steel material is exposed due to cracking of the hot-dip

[0015] steel material is exposed (for example, a cut end surface portion of the plated steel

15indicates a property First, the corrosion morphology of the Zn-Al-Mg-based plated layer was of inhibiting corrosion of the steel material at a portion where the

The "sacrificial corrosion resistance" described in the present specification

investigated. As a result, it was found that corrosion of the Zn-Al-Mg-based plated disappears, the steel material corrodes, resulting in the formation of red rust.

layer proceeded from the Zn-Al (β) phase. Furthermore, the present inventors have rust before the steel material corrodes, and after the plated layer turns into white rust and

found that this is because the Zn-Al (β) phase exhibits the electrochemically lowest corrosion process of a plated steel sheet, the plated layer corrodes and turns into white

7

corrosion potential (-1.3 V vs. Ag/AgCl in 1M NaCl aqueous solution) in the plated

20 layer.

[0016]

Furthermore, it was observed that, in the Zn-Al-Mg-based plated layer, after

corrosion proceeds from the Zn-Al (β) phase, the MgZn2 phase is subsequently corroded.

The corrosion potential of the MgZn2 phase was (-1.1 V vs. Ag/AgCl in 1M NaCl

25 aqueous solution). The β phase is distributed throughout the plated layer, and it is cooling rate, the Zn-A1 (ß) phase can be sufficiently formed, and the Zn-Cu phase formed 8 specific temperature region. Therefore, in such a temperature region, by reducing the effective to increase the potential of the Zn-Al (β) phase, which is a corrosion-prone During plating solidification, the Zn-Al (ß) phase is formed and grows in a

[0020] portion, for improving the external appearance and corrosion resistance.

[0017] plating is referred to as a "two-stage plating method".

the plating original sheet and then sequentially performing Zn-Al-Mg-based hot-dip

In order to increase the potential of the β phase, it is preferable that an described above, a method for forming a predetermined pre-plated layer in advance on

5may be contained) electrochemically to form a hot-dip noble element plating layer. In the is contained present in the specification, as Zn-Al (β) phase. Examples of an

element effective for increasing the potential of the β phase include Cu and Ag. substrate is immersed in a Zn-Al-Mg-based hot-dip plating bath (in which Cu and Ag This is plated to allow diffusion of Cu and/or Ag into the Zn-plated layer. Thereafter, the plated

because Cu and Ag have atomic radii similar to those of Al and Zn, respectively, form prepared by heating the plating original sheet on which Zn and Cu or Ag have been

substitutional solid solutions, and are easily mixed with each other. with Cu or Ag. Cu or Ag may be an alloy thereof. Subsequently, a plated substrate is

[0018] A plating original sheet is first electro-plated with Zn, and then electro-plated

[0019]

10 Examples of a suitable method for containing Cu or Ag in the Zn-Al (β) phase within the plated layer include the following two-stage plating method.

within the Examples of plated layer a suitable methodinclude the following for containing two-stage Cu or Ag in the plating method. Zn-Al (ß) phase

[0018]

[0019] substitutional solid solutions, and are easily mixed with each other.

A plating original sheet is first electro-plated with Zn, and then electro-plated because Cu and Ag have atomic radii similar to those of Al and Zn, respectively, form

with Cu or Ag. Cu or Ag may be an alloy thereof. Subsequently, a plated substrate is element effective for increasing the potential of the ß phase include Cu and Ag. This is

15electrochemically preparednoble by heating the plating original sheet on which Zn and Cu or Ag have been element is contained in the Zn-Al (ß) phase. Examples of an

In order to increase the potential of the ß phase, it is preferable that an

plated to allow diffusion of Cu and/or Ag into the Zn-plated layer. Thereafter, the plated

[0017]

substrate is immersed in a Zn-Al-Mg-based hot-dip plating bath (in which Cu and Ag portion, for improving the external appearance and corrosion resistance.

may be contained) to form a hot-dip plating layer. In the present specification, as effective to increase the potential of the Zn-Al (ß) phase, which is a corrosion-prone

8

described above, a method for forming a predetermined pre-plated layer in advance on

20 the plating original sheet and then sequentially performing Zn-Al-Mg-based hot-dip

plating is referred to as a “two-stage plating method”.

[0020]

During plating solidification, the Zn-Al (β) phase is formed and grows in a

specific temperature region. Therefore, in such a temperature region, by reducing the

25 cooling rate, the Zn-Al (β) phase can be sufficiently formed, and the Zn-Cu phase formed includes, in terms of mass%, 9 surface of the steel material. The average chemical composition of the plated layer on the surface of the plated substrate can be dissolved and contained in the Zn-Al (β) dip plated steel material including a steel material and a plated layer disposed on a phase. The hot-dip plated steel material according to the present embodiment is a hot-

[0021] will be described.

Hereinafter, a hot-dip plated steel material according to the present embodiment

As described above, in the plated layer containing Cu and Ag thus formed, the

[Hot-Dip Plated Steel Material]

5[0023] atomic positions of Zn are substantially identical to those of Cu and Ag, while the

distribution of these atoms differs from the component distribution of Al within the itself inconspicuous.

white rust is uniformly generated, so that it is possible to make the white rust generation

plated layer. plated steel material decreases. In addition, even though white rust is generated, the

[0022] portion decreases, the amount of white rust formed at the initial stage of corrosion in the

In the plated layer according to the present embodiment, Cu and Ag that exhibit with that of the MgZn phase. As a result, since the potential difference at a specific

Therefore, the potential distribution of the entire plated layer is substantially uniform

10 noble potentials are efficiently contained in the Zn-Al (β) phase, which is the most corrosion-prone portion, resulting in an increase in the corrosion potential of the ß phase.

corrosion-prone portion, resulting in an increase in the corrosion potential of the β phase. noble potentials are efficiently contained in the Zn-Al (ß) phase, which is the most

Therefore, the potential distribution of the entire plated layer is substantially uniform In the plated layer according to the present embodiment, Cu and Ag that exhibit

[0022]

with that of the MgZn2 phase. As a result, since the potential difference at a specific plated layer.

portion decreases, the amount of white rust formed at the initial stage of corrosion in the distribution of these atoms differs from the component distribution of Al within the

15atomic positions plated ofsteel material decreases. In addition, even though white rust is generated, the Zn are substantially identical to those of Cu and Ag, while the

As described above, in the plated layer containing Cu and Ag thus formed, the

[0021]

phase. itself inconspicuous.

[0023] on the surface of the plated substrate can be dissolved and contained in the Zn-Al (ß)

9

[Hot-Dip Plated Steel Material]

20 Hereinafter, a hot-dip plated steel material according to the present embodiment

will be described.

The hot-dip plated steel material according to the present embodiment is a hot-

dip plated steel material including a steel material and a plated layer disposed on a

surface of the steel material. The average chemical composition of the plated layer

25 includes, in terms of mass%,

0% or more and 0.25% or less of V, 10 0% or more and 0.25% or less of Co,

more than 10.0% and less than 45.0% of Al, 0% or more and 0.25% or less of Ti,

4.0% or more and 15.0% or less of Mg, 0% or more and 0.5% or less of P,

0.01% or more and 2.0% or less of Si, and 0% or more and 0.5% or less of B,

0% or more and 0.25% or less of Pb,

at least one of 0.03% or more and 5.0% or less of Cu, or 0.03% or more and 0% or more and 0.25% or less of Sb,

5 6.0% 0% or or less more and of 0.3%Ag, andof Mo, or less

further includes 0% or more and 0.5% or less of Cr,

0% or more and 1.0% or less of Ni,

0% or more and 0.7% or less of Sn, 0% or more and 0.3% or less of Li,

0% or more and 0.3% or less of Bi, 0% or more and 0.3% or less of Sr,

0% or more and 0.3% or less of In, 0% or more and 0.3% or less of Ce,

0% or more and 0.3% or less of La,

10 0% or more and 0.6% or less of Ca, 0% or more and 0.3% or less of Y,

0% or more and 0.3% or less of Y, 0% or more and 0.6% or less of Ca,

0% or more and 0.3% or less of La, 0% or more and 0.3% or less of In,

0% or more and 0.3% or less of Bi,

0% or more and 0.3% or less of Ce, 0% or more and 0.7% or less of Sn,

0% or more and 0.3% or less of Sr, further includes

156.0% or less of Ag,0% or more and 0.3% or less of Li, and

at least one of 0.03% or more and 5.0% or less of Cu, or 0.03% or more and

0% or more and 1.0% or less of Ni, 0.01% or more and 2.0% or less of Si, and

0% or more and 0.5% or less of Cr, 4.0% or more and 15.0% or less of Mg,

0% or more and 0.3% or less of Mo, more than 10.0% and less than 45.0% of Al,

10

0% or more and 0.25% or less of Sb,

20 0% or more and 0.25% or less of Pb,

0% or more and 0.5% or less of B,

0% or more and 0.5% or less of P,

0% or more and 0.25% or less of Ti,

0% or more and 0.25% or less of Co,

25 0% or more and 0.25% or less of V, for example, a hot-rolled steel sheet defined in JIS G 3131 (2018) and a cold-rolled steel 11 steel wire rods for bridge cables are applicable. More specifically, as the steel material,

0% or more and 0.25% or less of Nb, containing a corrosion resistance reinforcing element such as Ni or Cr), steels for bolts,

0% or more and 0.25% or less of Mn, carbon steel, various high tensile strength steels, some high alloy steels (a steel

0% or more and 0.25% or less of Zr, which various metals are thinly plated, an Al killed steel, an ultra low carbon steel, a high

material, for example, various steel sheets such as a general steel, a pre-plated steel in

0% or more and 0.25% or less of W, The material of the steel material is not particularly limited. As the steel

5[0025] 0% or more and 5.0% or less of Fe, and

a remainder of Zn and impurities, and steel sheet is not limited thereto.

of 10 mm or less and a sheet width of 2000 mm or less can be applied, but the size of the

the total amount of Cu and Ag satisfies 0.03% or more and 6.0% or less. to this. As the size of the steel sheet, for example, a steel sheet having a sheet thickness

[0024] immersion in molten metal, such as a continuous hot-dip galvanizing line (CGL), apply

(Steel Material) galvanizing step. In particular, steel sheets applicable in a step of solidification by

particularly limited. The steel sheet may be a steel sheet applicable to a general hot-dip

10 First, a steel material (original sheet) to be plated will be described. The steel material is, for example, mainly a steel sheet, but its size is not

The steel material is, for example, mainly a steel sheet, but its size is not First, a steel material (original sheet) to be plated will be described.

particularly (Steel Material) limited. The steel sheet may be a steel sheet applicable to a general hot-dip

[0024]

galvanizing step. In particular, steel sheets applicable in a step of solidification by the total amount of Cu and Ag satisfies 0.03% or more and 6.0% or less.

immersion inZnmolten a remainder of metal,and and impurities, such as a continuous hot-dip galvanizing line (CGL), apply

15 to0%this. As the size of the steel sheet, for example, a steel sheet having a sheet thickness or more and 5.0% or less of Fe, and

0% or more and 0.25% or less of W,

of 10 mm or less and a sheet width of 2000 mm or less can be applied, but the size of the 0% or more and 0.25% or less of Zr,

steel 0% orsheet is 0.25% more and not limited or less ofthereto. Mn,

[0025] 0% or more and 0.25% or less of Nb,

11

The material of the steel material is not particularly limited. As the steel

20 material, for example, various steel sheets such as a general steel, a pre-plated steel in

which various metals are thinly plated, an Al killed steel, an ultra low carbon steel, a high

carbon steel, various high tensile strength steels, some high alloy steels (a steel

containing a corrosion resistance reinforcing element such as Ni or Cr), steels for bolts,

steel wire rods for bridge cables are applicable. More specifically, as the steel material,

25 for example, a hot-rolled steel sheet defined in JIS G 3131 (2018) and a cold-rolled steel even in a case where the plated layer of the present embodiment is formed as a thin film, 12 example, a thickness of about a half of the conventional Zn-plated layer). Similarly, sheet defined in JIS G 3141 (2017), a steel material included in a general structural rolled conventional Zn-plated layer even though the plated layer is formed as a thin film (for steel material corresponding to a so-called SS material, a so-called general steel included containing the Zn phase can exhibit corrosion resistance equivalent to that of a in a hot-rolled steel sheet defined in JIS G 3193 (2019), pre-plated steels in which the Zn phase, corrosion resistance is improved. Therefore, such a plated layer based alloy layer. In a case where an alloying element such as Al or Mg is contained in various metals are thinly plated described in JIS H 8641 (2021), JIS G 3302 (2019), JIS The plated layer according to the present embodiment includes a Zn-Al-Mg-

5 GNext, 3303 the (2017), plated layerJIS G 3313 provided (2017), on the steel JIS material willGbe 3314 (2019), JIS G 3315 (2017), JIS G 3317 described.

(2019), JIS G 3321 (2019), and the like, a rolled steel material for structural use in (Plated Layer)

[0027]

buildings described in JIS G 3136 (2012), Al killed steel described in JIS G 3126 (2015), hot rolling step, a pickling step, a cold rolling step, and a heat treatment step.

ultra low carbon steel, high carbon steel, various high tensile strength steels described in such as an iron making and steelmaking step by a blast furnace or an electric furnace, a

JIS G 3113 (2018), JIS G 3134 (2018), and JIS G 3135 (2018), and some of high alloy Examples of a step of manufacturing the steel material include general steps

[0026]

10 steels (for example, steels containing corrosion resistance-enhancing elements such as Ni and Cr) are applicable.

and Cr) are applicable. steels (for example, steels containing corrosion resistance-enhancing elements such as Ni

[0026] JIS G 3113 (2018), JIS G 3134 (2018), and JIS G 3135 (2018), and some of high alloy

ultra low carbon steel, high carbon steel, various high tensile strength steels described in

Examples of a step of manufacturing the steel material include general steps buildings described in JIS G 3136 (2012), Al killed steel described in JIS G 3126 (2015),

such as an iron making and steelmaking step by a blast furnace or an electric furnace, a (2019), JIS G 3321 (2019), and the like, a rolled steel material for structural use in

15G 3303 hot rolling step, a pickling step, a cold rolling step, and a heat treatment step. (2017), JIS G 3313 (2017), JIS G 3314 (2019), JIS G 3315 (2017), JIS G 3317

various metals are thinly plated described in JIS H 8641 (2021), JIS G 3302 (2019), JIS

[0027] in a hot-rolled steel sheet defined in JIS G 3193 (2019), pre-plated steels in which

(Plated Layer) steel material corresponding to a so-called SS material, a so-called general steel included

Next, the plated layer provided on the steel material will be described. sheet defined in JIS G 3141 (2017), a steel material included in a general structural rolled

12

The plated layer according to the present embodiment includes a Zn-Al-Mg-

20 based alloy layer. In a case where an alloying element such as Al or Mg is contained in

the Zn phase, corrosion resistance is improved. Therefore, such a plated layer

containing the Zn phase can exhibit corrosion resistance equivalent to that of a

conventional Zn-plated layer even though the plated layer is formed as a thin film (for

example, a thickness of about a half of the conventional Zn-plated layer). Similarly,

25 even in a case where the plated layer of the present embodiment is formed as a thin film, may be subjected to high processing when used as a member or the like. Specifically, 13 Fe-based interfacial alloy layer is as thin as possible in a hot-dip plated steel material that corrosion resistance equal to or higher than that of the conventional Zn-plated layer is improving powdering resistance. Therefore, it is preferable that the thickness of the Al- ensured. number of crack initiation sites in the plated layer during processing, thereby further

[0028] Usually, an Al-Fe-based interfacial alloy layer having a thin thickness can reduce the

resistance indicating the degree of peeling of the plated layer during processing.

The Zn-Al-Mg-based alloy layer is made of a Zn-Al-Mg-based alloy. The Zn- material. In particular, the Al-Fe-based interfacial alloy layer may affect powdering

5absence Al-Mg-based alloy of cracks) of the plated means layer a ternary during processing alloy of the hot-dipcontaining plated steel Zn, Al, and Mg.

[0029] corrosion resistance, but has an influence on adhesion and workability (presence or

The Al-Fe-based interfacial alloy layer does not have a large influence on

The plated layer may include an Al-Fe-based interfacial alloy layer (with a

[0030]

thickness of less than 5 μm). The Al-Fe-based interfacial alloy layer is an interfacial alloy layer is preferably a layer constituting a surface of the plated layer.

alloy layer between the steel material and the Zn-Al-Mg-based alloy layer, and is in Al-Fe-based interfacial alloy layer. For the stacked layer structure, the Zn-Al-Mg-based

alloy layer or a stacked layer structure including the Zn-Al-Mg-based alloy layer and the

10 contact with a surface of the steel material. That is, the plated layer according to the present embodiment may have a single-layer structure formed of the Zn-Al-Mg-based

present embodiment may have a single-layer structure formed of the Zn-Al-Mg-based contact with a surface of the steel material. That is, the plated layer according to the

alloy layer or a stacked layer structure including the Zn-Al-Mg-based alloy layer and the alloy layer between the steel material and the Zn-Al-Mg-based alloy layer, and is in

thickness of less than 5 µm). The Al-Fe-based interfacial alloy layer is an interfacial

Al-Fe-based interfacial alloy layer. For the stacked layer structure, the Zn-Al-Mg-based The plated layer may include an Al-Fe-based interfacial alloy layer (with a

[0029] alloy layer is preferably a layer constituting a surface of the plated layer.

15Al-Mg-based

[0030] alloy means a ternary alloy containing Zn, Al, and Mg.

The Zn-Al-Mg-based alloy layer is made of a Zn-Al-Mg-based alloy. The Zn-

The Al-Fe-based interfacial alloy layer does not have a large influence on

[0028]

ensured. corrosion resistance, but has an influence on adhesion and workability (presence or

absence of cracks) of the plated layer during processing of the hot-dip plated steel corrosion resistance equal to or higher than that of the conventional Zn-plated layer is

13

material. In particular, the Al-Fe-based interfacial alloy layer may affect powdering

20 resistance indicating the degree of peeling of the plated layer during processing.

Usually, an Al-Fe-based interfacial alloy layer having a thin thickness can reduce the

number of crack initiation sites in the plated layer during processing, thereby further

improving powdering resistance. Therefore, it is preferable that the thickness of the Al-

Fe-based interfacial alloy layer is as thin as possible in a hot-dip plated steel material that

25 may be subjected to high processing when used as a member or the like. Specifically, the interface may also be contained in the Al-Fe-based interfacial alloy layer. 14 Al-Fe-based interfacial alloy layer. A small amount of Si that is likely to accumulate at the thickness of an intermetallic compound constituting the Al-Fe-based interfacial alloy is also contained in the plating bath, a small amount of Zn may also be contained in the layer is less than 5 μm. The thickness is preferably 2 μm or less, more preferably 1 μm contained in the Al-Fe-based interfacial alloy layer. Since a certain concentration of Zn or less, and still more preferably 0.5 μm or less. amount of an AlFe phase, an AlFe phase, an AlFe phase, or the like may be partially The thickness may be 0.3 μm or less. concentration may be high in a portion close to the base metal. Therefore, a small

As a result, the occurrence of cracks during processing can be minimized, and the concentration in the Al-Fe-based interfacial alloy layer is not uniform, and the Fe

5interfacial powdering alloy layer. resistance can However, since it betimefurther takes improved. to diffuse atoms, the Fe Furthermore, a ratio of the thickness of

the Al-Fe-based interfacial alloy layer to the thickness of the plated layer is less than 10% plating bath, the AlFe phase is the predominant phase formed in the Al-Fe-based

the present embodiment, since a certain concentration or more of Al is contained in the

on average, more preferably less than 5%. interfacial alloy layer is easily formed in the plated layer containing an Al element. In

[0031] case where a continuous hot-dip plating method is used as a procedure, the Al-Fe-based

The Al-Fe-based interfacial alloy layer is formed on a surface of the steel mutual atomic diffusion between the base metal (steel sheet) and the plating bath. In a

phase as the microstructure. The Al-Fe-based interfacial alloy layer is formed by

10 material, specifically, between the steel material and the Zn-Al-Mg-based alloy layer. The Al-Fe-based interfacial alloy layer is a layer in which an AlFe phase is the main

The Al-Fe-based interfacial alloy layer is a layer in which an Al5Fe2 phase is the main material, specifically, between the steel material and the Zn-Al-Mg-based alloy layer.

phase as the microstructure. The Al-Fe-based interfacial alloy layer is formed by The Al-Fe-based interfacial alloy layer is formed on a surface of the steel

[0031]

mutual atomic diffusion between the base metal (steel sheet) and the plating bath. In a on average, more preferably less than 5%.

case where a continuous hot-dip plating method is used as a procedure, the Al-Fe-based the Al-Fe-based interfacial alloy layer to the thickness of the plated layer is less than 10%

15powdering interfacial alloy layer is easily formed in the plated layer containing an Al element. In resistance can be further improved. Furthermore, a ratio of the thickness of

As a result, the occurrence of cracks during processing can be minimized, and the

the present embodiment, since a certain concentration or more of Al is contained in the or less, and still more preferably 0.5 µm or less. The thickness may be 0.3 µm or less.

plating bath, the Al Fe phase is the predominant phase formed in the Al-Fe-based 5 2 is preferably 2 µm or less, more preferably 1 µm layer is less than 5 µm. The thickness

interfacial alloy layer. However, since it takes time to diffuse atoms, the Fe the thickness of an intermetallic compound constituting the Al-Fe-based interfacial alloy

14

concentration in the Al-Fe-based interfacial alloy layer is not uniform, and the Fe

20 concentration may be high in a portion close to the base metal. Therefore, a small

amount of an AlFe phase, an Al3Fe phase, an Al5Fe2 phase, or the like may be partially

contained in the Al-Fe-based interfacial alloy layer. Since a certain concentration of Zn

is also contained in the plating bath, a small amount of Zn may also be contained in the

Al-Fe-based interfacial alloy layer. A small amount of Si that is likely to accumulate at

25 the interface may also be contained in the Al-Fe-based interfacial alloy layer.

total average chemical composition of the Al-Fe-based interfacial alloy layer and the Zn- 15 Mg-based alloy layer, the average chemical composition of the entire plated layer is the

[0032] stacked layer structure including the Al-Fe-based interfacial alloy layer and the Zn-Al-

In the present embodiment, the plated layer contains Si. composition of the Zn-Al-Mg-based alloy layer. In a case where the plated layer has a Si is partially

incorporated into the Al-Fe-based interfacial alloy layer to form an Al-Fe-Si intermetallic layer, the average chemical composition of the entire plated layer is the average chemical

In a case where the plated layer has a single-layer structure of the Zn-Al-Mg-based alloy

compound phase. One of the identified intermetallic compound phases is an AlFeSi Next, the average chemical composition of the plated layer will be described.

5[0034] phase. Examples of the isomer of the AlFeSi phase include an α phase, a β phase, a q1

phase, and a q2 phase. Therefore, these AlFeSi phases and the like may be detected in the present embodiment may be, for example, 100 µm or less.

100 µm or less. Therefore, the plating thickness of the hot-dip plated steel material of

the Al-Fe-based interfacial alloy layer. The Al-Fe-based interfacial alloy layer thickness of the plated layer formed by the continuous hot-dip plating method is often

containing these AlFeSi phases and the like is also referred to as an Al-Fe-Si alloy layer. the case of the continuous hot-dip plating method. The absolute maximum value of the

[0033] entire plated layer is affected by the viscosity and specific gravity of the plating bath in

material from the plating bath and the wiping conditions. That is, the thickness of the

10 The upper limit and the lower limit of the thickness of the entire plated layer are not particularly limited. The thickness is also affected by the drawing speed of the steel

not Theparticularly limited. upper limit and the The lower limit of thickness the thickness of the is alsoplated entire affected layer areby the drawing speed of the steel

[0033] material from the plating bath and the wiping conditions. That is, the thickness of the containing these AlFeSi phases and the like is also referred to as an Al-Fe-Si alloy layer.

entire plated layer is affected by the viscosity and specific gravity of the plating bath in the Al-Fe-based interfacial alloy layer. The Al-Fe-based interfacial alloy layer

the case of the continuous hot-dip plating method. The absolute maximum value of the phase, and a q2 phase. Therefore, these AlFeSi phases and the like may be detected in

15phase. thickness of the plated layer formed by the continuous hot-dip plating method is often Examples of the isomer of the AlFeSi phase include an phase, a ß phase, a q1

compound phase. One of the identified intermetallic compound phases is an AlFeSi

100 μm or less. Therefore, the plating thickness of the hot-dip plated steel material of incorporated into the Al-Fe-based interfacial alloy layer to form an Al-Fe-Si intermetallic

theIn present the present embodiment may embodiment, the plated layerbe, for Si. contains example, 100 μm or less. Si is partially

[0032]

[0034] 15

Next, the average chemical composition of the plated layer will be described.

20 In a case where the plated layer has a single-layer structure of the Zn-Al-Mg-based alloy

layer, the average chemical composition of the entire plated layer is the average chemical

composition of the Zn-Al-Mg-based alloy layer. In a case where the plated layer has a

stacked layer structure including the Al-Fe-based interfacial alloy layer and the Zn-Al-

Mg-based alloy layer, the average chemical composition of the entire plated layer is the

25 total average chemical composition of the Al-Fe-based interfacial alloy layer and the Zn- sheet according to the present embodiment. In a case where the Mg content in the 16 an important element for improving sacrificial corrosion resistance in the plated steel

Al-Mg-based alloy layer. Similarly to Zn, Mg is an element mainly constituting the plated layer. Mg is

[0035] Mg: 4.0% Or More and 15.0% Or Less

[0037] In the plated layer of the present embodiment, the thickness of the Al-Fe-based than 45%.

interfacial alloy layer is preferably 10% or less with respect to the thickness of the entire the Al-Zn (ß) phase is not formed. Therefore, the upper limit of the Al content is less

5contentplated is 45.0%layer. or more, In the a case() where Al-Zn phase is the thickness mainly of plated formed in the the Al-Fe-based layer, and interfacial alloy layer is

sufficiently small with respect to the entire plated layer as described above, the Fe Therefore, the Al content is more than 10%. On the other hand, in a case where the Al

content is 10% or less, a sufficient amount of a Zn-Al phase may not be ensured.

concentration of the plated layer is often 5% or less. Therefore, the average chemical Al is an element mainly constituting the plated layer. In a case where the Al

composition Al: More Than of theand 10.0% plated Less layer is approximately the same as the components of the Zn- Than 45.0%

[0036] Al-Mg-based alloy layer. Furthermore, traces of a plating raw material are less likely to bath used for manufacture.

10 remain as chemical components of the plated layer. Therefore, the average chemical composition of the plated layer is substantially equal to the components of the plating

composition of the plated layer is substantially equal to the components of the plating remain as chemical components of the plated layer. Therefore, the average chemical

bath used for manufacture. Al-Mg-based alloy layer. Furthermore, traces of a plating raw material are less likely to

composition of the plated layer is approximately the same as the components of the Zn-

[0036] concentration of the plated layer is often 5% or less. Therefore, the average chemical

Al: More Than 10.0% and Less Than 45.0% sufficiently small with respect to the entire plated layer as described above, the Fe

15plated layer. In a case Alwhere is an element mainly constituting the plated layer. In a case where the Al the thickness of the Al-Fe-based interfacial alloy layer is

interfacial alloy layer is preferably 10% or less with respect to the thickness of the entire

content is 10% or less, a sufficient amount of a Zn-Al phase may not be ensured. In the plated layer of the present embodiment, the thickness of the Al-Fe-based

[0035] Therefore, the Al content is more than 10%. On the other hand, in a case where the Al

content is 45.0% or more, the Al-Zn (α) phase is mainly formed in the plated layer, and Al-Mg-based alloy layer.

16

the Al-Zn (β) phase is not formed. Therefore, the upper limit of the Al content is less

20 than 45%.

[0037]

Mg: 4.0% Or More and 15.0% Or Less

Similarly to Zn, Mg is an element mainly constituting the plated layer. Mg is

an important element for improving sacrificial corrosion resistance in the plated steel

25 sheet according to the present embodiment. In a case where the Mg content in the

[0039] 17 0.30%. In a case where the Si content is 2.0% or less, MgSi is less likely to be formed.

plated layer is less than 4.0%, the improvement effect of sacrificial corrosion resistance is 2.0% or less. The preferable range is 0.10% to 0.40%, and more preferably 0.20% to

not clearly observed as compared with the case where Mg is not contained. appearance is significantly deteriorated. Therefore, the upper limit of the Si content is Therefore,

the Mg content is 4.0% or more. In contrast, in a case where Mg is excessively added in bath, and the thickness of the plated layer is extremely thin. In addition, the plating

metal to the steel material is reduced when the steel material is pulled up from the plating

the Zn-Al-Mg-based plating bath, a rapid oxidation reaction occurs on a bath surface of extremely high viscosity of the plating bath. Therefore, the adhesion amount of molten

5in which theMg plating bath, reacts with Si toand form plating cannot MgSi is formed in a be stably large performed. amount, resulting in theTherefore, in order to stably

perform plating and ensure good manufacturability, the Mg content in the plated layer is where the Si content is 2.0% or more, an intermetallic compound having a composition

growth rate of the thickness of the interfacial alloy layer is reduced. However, in a case

15% or less. impaired. On the other hand, in a case where the Si content is 0.01% or more, the

[0038] increases, powdering occurs during processing, and corrosion resistance is significantly

Si: 0.01% Or More and 2.0% Or Less contained, the Al-Fe reaction becomes active, the thickness of the Al-Fe alloy layer

interfacial alloy layer to form an Al-Fe-Si compound. In a case where Si is not

10 Si suppresses an Al-Fe reaction, thereby inhibiting the formation of an Al-Fe- based interfacial alloy layer. In addition, Si is incorporated into part of the Al-Fe-based

based interfacial Si suppresses alloy layer. an Al-Fe reaction, In addition, thereby inhibiting Si ofisanincorporated the formation Al-Fe- into part of the Al-Fe-based

interfacial alloy layer to form an Al-Fe-Si compound. In a case where Si is not Si: 0.01% Or More and 2.0% Or Less

[0038]

contained, the Al-Fe reaction becomes active, the thickness of the Al-Fe alloy layer 15% or less.

increases, powdering occurs during processing, and corrosion resistance is significantly perform plating and ensure good manufacturability, the Mg content in the plated layer is

15the plating impaired. On the other hand, in a case where the Si content is 0.01% or more, the bath, and plating cannot be stably performed. Therefore, in order to stably

the Zn-Al-Mg-based plating bath, a rapid oxidation reaction occurs on a bath surface of

growth rate of the thickness of the interfacial alloy layer is reduced. However, in a case the Mg content is 4.0% or more. In contrast, in a case where Mg is excessively added in

where the Si content is 2.0% or more, an intermetallic compound having a composition not clearly observed as compared with the case where Mg is not contained. Therefore,

in which Mg reacts with Si to form Mg2Si is formed in a large amount, resulting in the plated layer is less than 4.0%, the improvement effect of sacrificial corrosion resistance is

17

extremely high viscosity of the plating bath. Therefore, the adhesion amount of molten

20 metal to the steel material is reduced when the steel material is pulled up from the plating

bath, and the thickness of the plated layer is extremely thin. In addition, the plating

appearance is significantly deteriorated. Therefore, the upper limit of the Si content is

2.0% or less. The preferable range is 0.10% to 0.40%, and more preferably 0.20% to

0.30%. In a case where the Si content is 2.0% or less, Mg2Si is less likely to be formed.

25 [0039] elements also exhibit very low electrochemical nobility, and thus provide a high 18 containment of these elements in the plated layer clearly improves workability. These

Since Cu and Ag have atomic radii similar to those of Zn and Al, Cu and Ag are These elements are softer than the MgZn phase and have good workability, so that

easily mixed by being substituted with these elements in the plated layer. to be formed in the plated layer. Bi forms MgBi, and In forms MgIn, for example. Since Cu and

Ag are contained in the plated layer, the potential of the Zn-Al (β) phase increases, and optionally contained, each content is 0% or more. When Sn is contained, Mg9Sn tends

when contained in the plated layer. Since Sn, Bi, and In are elements that can be

corrosion resistance is improved. Cu and Ag have almost the same action. In order to Each of Sn, Bi, and In is an element that promotes softening of the plated layer

5 change the In: 0% or potential more and 0.3% orand lesschange the initial white rust formation behavior, it is effective

that the plated layer contains at least one of Cu or Ag in an amount of 0.03% or more. Bi: 0% or more and 0.3% or less

Sn: 0% or more and 0.7% or less

Preferably, the total concentration of Cu and Ag in the plated layer is 0.4% or more. In

[0040]

contrast, in a case where the contents of Cu and Ag are excessive, an electrically noble by Cu and Ag that cannot be contained in the ß phase, thereby promoting corrosion.

portion may be formed by Cu and Ag that cannot be contained in the β phase, thereby case where the total amount of Cu and Ag is 6.0%, an electrically noble portion is formed

contained, the upper limit of the total amount of Cu and Ag is 6%. This is because in a

10 promoting corrosion. Therefore, the upper limit of the Cu content is 5.0% or less, and the upper limit of the Ag content is 6.0% or less. In a case where Cu and Ag are both

the upper limit of the Ag content is 6.0% or less. In a case where Cu and Ag are both promoting corrosion. Therefore, the upper limit of the Cu content is 5.0% or less, and

contained, the upper limit of the total amount of Cu and Ag is 6%. portion may be formed by Cu and Ag that cannot be contained in the ß phase, thereby This is because in a contrast, in a case where the contents of Cu and Ag are excessive, an electrically noble

case where the total amount of Cu and Ag is 6.0%, an electrically noble portion is formed Preferably, the total concentration of Cu and Ag in the plated layer is 0.4% or more. In

by Cu and Ag that cannot be contained in the β phase, thereby promoting corrosion. that the plated layer contains at least one of Cu or Ag in an amount of 0.03% or more.

15change the

[0040] potential and change the initial white rust formation behavior, it is effective

corrosion resistance is improved. Cu and Ag have almost the same action. In order to

Sn: 0% or more and 0.7% or less Ag are contained in the plated layer, the potential of the Zn-Al (ß) phase increases, and

Bi: 0% or more and 0.3% or less easily mixed by being substituted with these elements in the plated layer. Since Cu and

In: 0% or more and 0.3% or less Since Cu and Ag have atomic radii similar to those of Zn and Al, Cu and Ag are

18

Each of Sn, Bi, and In is an element that promotes softening of the plated layer

20 when contained in the plated layer. Since Sn, Bi, and In are elements that can be

optionally contained, each content is 0% or more. When Sn is contained, Mg9Sn5 tends

to be formed in the plated layer. Bi forms Mg3Bi2, and In forms Mg3In, for example.

These elements are softer than the MgZn2 phase and have good workability, so that

containment of these elements in the plated layer clearly improves workability. These

25 elements also exhibit very low electrochemical nobility, and thus provide a high form an intermetallic compound with Si, Zn, Al, or the like. However, in a case where 19 Ca, Y, La, Ce, Sr, Li, Ni, Cr, Mo, Sb, Pb, B, P, Ti, Co, V, Nb, Mn, Zr, and W all sacrificial anticorrosion effect. By containing at least one of Sn, Bi, and In, the effect of W: 0% or more and 0.25% or less improving worked Zr: 0% or more portion and 0.25% or less corrosion resistance can be obtained.

[0041] Mn: 0% or more and 0.25% or less

Nb: 0% or more and 0.25% or less

Ca: 0% or more and 0.6% or less V: 0% or more and 0.25% or less

5 Y: 0% or more and 0.3% or less Co: 0% or more and 0.25% or less

La: 0% or more and 0.3% or less Ti: 0% or more and 0.25% or less

P: 0% or more and 0.5% or less

Ce: 0% or more and 0.3% or less B: 0% or more and 0.5% or less

Sr: 0% or more and 0.3% or less Pb: 0% or more and 0.25% or less

Li: 0% or more and 0.3% or less Sb: 0% or more and 0.25% or less

Mo: 0% or more and 0.3% or less

10 Ni: 0% or more and 1.0% or less Cr: 0% or more and 0.5% or less

Cr: 0% or more and 0.5% or less Ni: 0% or more and 1.0% or less

Mo: 0% or more and 0.3% or less Li: 0% or more and 0.3% or less

Sr: 0% or more and 0.3% or less

Sb: 0% or more and 0.25% or less Ce: 0% or more and 0.3% or less

Pb: 0% or more and 0.25% or less La: 0% or more and 0.3% or less

15 B: 0% or more and 0.5% or less Y: 0% or more and 0.3% or less

Ca: 0% or more and 0.6% or less

P: 0% or more and 0.5% or less

[0041]

Ti: 0% or more and 0.25% or less improving worked portion corrosion resistance can be obtained.

Co: 0% or more and 0.25% or less sacrificial anticorrosion effect. By containing at least one of Sn, Bi, and In, the effect of

19

V: 0% or more and 0.25% or less

20 Nb: 0% or more and 0.25% or less

Mn: 0% or more and 0.25% or less

Zr: 0% or more and 0.25% or less

W: 0% or more and 0.25% or less

Ca, Y, La, Ce, Sr, Li, Ni, Cr, Mo, Sb, Pb, B, P, Ti, Co, V, Nb, Mn, Zr, and W all

25 form an intermetallic compound with Si, Zn, Al, or the like. However, in a case where mixed in the manufacturing step and not intentionally contained. For example, in the 20 The impurity refers to a component that is contained in the raw material or the contents of these elements are within the above-described range, the elements do not

[0044]

affect the initial corrosion of the plated layer. element constituting the main phase of the plated layer is Zn. In contrast, in a case where these

elements are excessively contained, a potential difference may be generated in the plated of the present embodiment is a highly versatile Zn-based plated steel material, the

The remainder preferably contains Zn. Since the hot-dip plated steel material

layer, and a large amount of initial white rust may be formed. Therefore, in the case Remainder: Zn and Impurities

5[0043] where these elements are contained, the contents thereof may be within the above-

described range. more than 0%.

limited to 5.0% or less. Therefore, the Fe content is 0 to 5.0%. The Fe content may be

[0042] occurrence of cracks and the like in the plated layer as long as the Fe concentration is

Fe: 0% Or More and 5.0% Or Less may be contained in the plated layer up to 5.0%, but Fe does not affect the frequency of

Since the hot-dip plated steel material of the present embodiment is interfacial alloy layer may be formed, but the thickness thereof is thin. As a result, Fe

present embodiment, the Al concentration of the plated layer is high, and the Al-Fe-based

10 manufactured by a continuous hot-dip plating method, Fe may be diffused into the plated layer from the plating raw material during manufacturing. As described above, in the

layer from the plating raw material during manufacturing. As described above, in the manufactured by a continuous hot-dip plating method, Fe may be diffused into the plated

present embodiment, the Al concentration of the plated layer is high, and the Al-Fe-based Since the hot-dip plated steel material of the present embodiment is

Fe: 0% Or More and 5.0% Or Less

interfacial alloy layer may be formed, but the thickness thereof is thin. As a result, Fe

[0042]

may be contained in the plated layer up to 5.0%, but Fe does not affect the frequency of described range.

15where these occurrence of cracks and the like in the plated layer as long as the Fe concentration is elements are contained, the contents thereof may be within the above-

layer, and a large amount of initial white rust may be formed. Therefore, in the case

limited to 5.0% or less. Therefore, the Fe content is 0 to 5.0%. The Fe content may be elements are excessively contained, a potential difference may be generated in the plated

more than 0%. affect the initial corrosion of the plated layer. In contrast, in a case where these

[0043] the contents of these elements are within the above-described range, the elements do not

20

Remainder: Zn and Impurities

20 The remainder preferably contains Zn. Since the hot-dip plated steel material

of the present embodiment is a highly versatile Zn-based plated steel material, the

element constituting the main phase of the plated layer is Zn.

[0044]

The impurity refers to a component that is contained in the raw material or

25 mixed in the manufacturing step and not intentionally contained. For example, in the of 5 mass% based on the Fe concentration distribution. Details of the GDS analysis 21 defined as a position at which the Fe concentration reaches a quantitative analysis value plated layer, a small amount of component other than Fe may be mixed as the impurity is defined as a start point (zero point), and the interface position of the plated layer is due to mutual atomic diffusion between the steel material (base metal) and the plating as well as on the definition. In the present embodiment, the surface of the plated layer bath. In addition, since a metal having a purity of 3 N is usually used for manufacturing or more, and the interface position also varies depending on the sputtering rate or the like

GDS is effective for grasping components in a relatively wide range of of several mm

a plating alloy, the concentration of impurities may be approximately 0.03% or less in layer, glow discharge optical emission spectrometry (GDS) is used. On the other hand,

5 total. For grasping the component distribution in the depth direction of the plated

[0045] direction will be described.

Next, the distribution of the components of the plated layer in the depth

In order to identify the average chemical composition of the plated layer, an acid

[0046]

solution is obtained in which the plated layer is peeled off and dissolved with an acid be obtained at the same time.

containing an inhibitor that inhibits corrosion of the base metal (steel material). weight before and after peeling are measured, a plating adhesion amount (g/m²) can also Next, limited as long as the acid can dissolve the plated layer. In a case where the area and

10 the obtained acid solution is measured by ICP emission spectrometry or an ICP-MS method to obtain the chemical composition. The type of the acid is not particularly

method to obtain the chemical composition. The type of the acid is not particularly the obtained acid solution is measured by ICP emission spectrometry or an ICP-MS

limited as long as the acid can dissolve the plated layer. In a case where the area and containing an inhibitor that inhibits corrosion of the base metal (steel material). Next,

solution is obtained in which the plated layer is peeled off and dissolved with an acid

weight before and after peeling are measured, a plating adhesion amount (g/m2) can also In order to identify the average chemical composition of the plated layer, an acid

[0045] be obtained at the same time.

15 [0046] total.

a plating alloy, the concentration of impurities may be approximately 0.03% or less in

Next, the distribution of the components of the plated layer in the depth bath. In addition, since a metal having a purity of 3 N is usually used for manufacturing

direction will be described. due to mutual atomic diffusion between the steel material (base metal) and the plating

For grasping the component distribution in the depth direction of the plated plated layer, a small amount of component other than Fe may be mixed as the impurity

21

layer, glow discharge optical emission spectrometry (GDS) is used. On the other hand,

20 GDS is effective for grasping components in a relatively wide range of φ of several mm

or more, and the interface position also varies depending on the sputtering rate or the like

as well as on the definition. In the present embodiment, the surface of the plated layer

is defined as a start point (zero point), and the interface position of the plated layer is

defined as a position at which the Fe concentration reaches a quantitative analysis value

25 of 5 mass% based on the Fe concentration distribution. Details of the GDS analysis

[0050] 22 layer increases.

conditions and the like will be described later. (degree) of such containment or substitution is uniform, the overall potential of the plated

[0047] phase or substitutes for Zn in the Zn-Al (ß) phase, which means that as the fraction

Although a FeAl-based compound may be generated in the interfacial alloy occupies the same site as Zn suggests that Cu or Ag is either contained in the Zn-A1 (ß)

plated layer. That is, the present inventors have found as follows: the fact that Cu or Ag

layer, the interface position in this case is on the interfacial alloy layer. According to electrochemically less noble Zn site leads to an increase in the corrosion potential of the

5 theTheabove-described definition,noble incorporation of electrochemically it is Cupossible or Ag intoto grasp the components focused only on the the

[0049] plated layer of the Zn-Al-Mg-based alloy layer excluding the interfacial alloy layer. In Al, and there is a case where there is no correlation with Zn.

a case where the thickness of the plated layer is denoted by t, the central part of the plated and Ag elements to a plating bath, Cu and Ag elements have distributions close to that of

layer can be regarded as 1/3 t to 2/3 t with respect to the thickness t of the plated layer. distribution. On the other hand, for example, for a plated layer formed by adding Cu

That is, a range of 1/3 t to 2/3 t is a main portion of the plated layer. bonded to or substituted with Zn in the depth direction, and thus have a similar The outline is In the plated layer of the present embodiment, Cu and Ag elements are mostly

10 illustrated in FIG. 1.

[0048]

[0048] illustrated in FIG. 1.

In the plated layer of the present embodiment, Cu and Ag elements are mostly That is, a range of 1/3 t to 2/3 t is a main portion of the plated layer. The outline is

layer can be regarded as 1/3 t to 2/3 t with respect to the thickness t of the plated layer.

bonded to or substituted with Zn in the depth direction, and thus have a similar a case where the thickness of the plated layer is denoted by t, the central part of the plated

distribution. On the other hand, for example, for a plated layer formed by adding Cu plated layer of the Zn-Al-Mg-based alloy layer excluding the interfacial alloy layer. In

15the above-described and Ag elements to a plating bath, Cu and Ag elements have distributions close to that of definition, it is possible to grasp the components focused only on the

layer, the interface position in this case is on the interfacial alloy layer. According to

Al, and there is a case where there is no correlation with Zn. Although a FeAl-based compound may be generated in the interfacial alloy

[0047] [0049]

The incorporation of electrochemically noble Cu or Ag into the conditions and the like will be described later.

22

electrochemically less noble Zn site leads to an increase in the corrosion potential of the

20 plated layer. That is, the present inventors have found as follows: the fact that Cu or Ag

occupies the same site as Zn suggests that Cu or Ag is either contained in the Zn-Al (β)

phase or substitutes for Zn in the Zn-Al (β) phase, which means that as the fraction

(degree) of such containment or substitution is uniform, the overall potential of the plated

layer increases.

25 [0050]

Expression (3). 0.01 CAZ and CAZ 0.08 are more preferable. As a result, 23 potential promotes corrosion. Therefore, CAZ needs to satisfy the following

The degree of substitution (CAZ) of Zn with Cu and/or Ag can be expressed by following Expression (2). On the other hand, an excessive increase in corrosion

theIn following Expression order to sufficiently increase the(5) in component potential, it is necessaryanalysis of GDS. to satisfy the

[0055]

[0051] CAZmax/CAZmin 1.20. (1) CAZ = [Cu + Ag]/[Zn]... (5)

[0054]

5CAZmax/CAZmin is preferably In Expression (5), [Cu], [Ag], and [Zn] are quantitative component analysis 1.1 or less.

values (mass%) in the depth direction in the GDS. sheet. This is because Cu and/or Ag are uniformly distributed in the plated layer.

plated layer, and the amount of white rust formed tends to decrease in the plated steel

[0052] Expression (1), an increase in corrosion potential in the plated layer occurs in the entire

“CAZ” is a ratio of the total concentration of the Cu concentration and the Ag CAZ of CAZ and the absolute minimum value CAZ of CAZ satisfy the following

concentration to the Zn concentration in the internal region between the 1/3 t position and In addition, in the plated layer, in a case where the absolute maximum value

[0053]

10 the 2/3 t position with respect to the surface of the plated layer. The larger the CAZ value is, the more substitution proceeds.

value is, the more substitution proceeds. the 2/3 t position with respect to the surface of the plated layer. The larger the CAZ

[0053] concentration to the Zn concentration in the internal region between the 1/3 t position and

"CAZ" is a ratio of the total concentration of the Cu concentration and the Ag

In addition, in the plated layer, in a case where the absolute maximum value

[0052]

CAZ max values (mass%) of CAZ and the absolute minimum value CAZmin of CAZ satisfy the following in the depth direction in the GDS.

15 Expression (1), an increase in corrosion potential in the plated layer occurs in the entire In Expression (5), [Cu], [Ag], and [Zn] are quantitative component analysis

CAZ = [Cu + Ag]/[Zn]... (5)

[0051]

sheet. This is because Cu and/or Ag are uniformly distributed in the plated layer. the following Expression (5) in component analysis of GDS.

CAZ max/CAZmin is preferably 1.1 or less. The degree of substitution (CAZ) of Zn with Cu and/or Ag can be expressed by

23

[0054]

20 CAZmax/CAZmin ≤ 1.20... (1)

[0055]

In order to sufficiently increase the potential, it is necessary to satisfy the

following Expression (2). On the other hand, an excessive increase in corrosion

potential promotes corrosion. Therefore, CAZmax needs to satisfy the following

25 Expression (3). 0.01 ≤ CAZmin and CAZmax ≤ 0.08 are more preferable. As a result,

[0059] 24 phase is increased, and corrosion resistance can be further improved.

the corrosion potential can be set to a potential almost equal to that of the MgZn2 phase phase. By satisfying the following Expression (4), the electrical resistance of the ß

present in a large amount in the plated layer, and the formation of white rust due to preferable to satisfy the following Expression (4) at any point or in any region in the ß

corrosion is minimized, so that the external appearance is further improved. having excellent corrosion resistance can be present in this range. In addition, it is

The ratio of Zn to Al (Zn : Al) in the ß phase is about 1 : 1, and the ß phase

[0056]

[0058]

5EPMA, or the like.0.0005 ≤ CAZmin... (2)

CAZmax ≤ 0.1000... (3) SEM. In addition, quantitative analysis values of the site can be obtained by EDS,

5 µm or more in the plated layer, the presence of the ß phase can be easily observed by

[0057] substitution of Al and Zn in the ß phase constant. Since the ß phase has a size of about

It is effective to increase the potential of the Zn-Al phase (β phase) for can be evaluated by the corrosion current density, and can be achieved by making the

deterioration of the external appearance due to the formation of white rust of the plated progression can be reduced and corrosion resistance can be improved. This tendency

furthermore, the electrical resistance of the ß phase itself is increased, corrosion

10 layer. In addition, in a case where the potential is increased to reduce the potential difference with the surrounding intermetallic compounds and the metal phases, and

difference with the surrounding intermetallic compounds and the metal phases, and layer. In addition, in a case where the potential is increased to reduce the potential

furthermore, the electrical resistance of the β phase itself is increased, corrosion deterioration of the external appearance due to the formation of white rust of the plated

It is effective to increase the potential of the Zn-Al phase (ß phase) for

progression can be reduced and corrosion resistance can be improved. This tendency

[0057]

can be evaluated CAZ 0.1000 by (3) the corrosion current density, and can be achieved by making the

0.0005 CAZ 15 substitution of Al (2) and Zn in the β phase constant. Since the β phase has a size of about

[0056]

5 μm or more in the plated layer, the presence of the β phase can be easily observed by corrosion is minimized, so that the external appearance is further improved.

SEM. In addition, quantitative analysis values of the site can be obtained by EDS, present in a large amount in the plated layer, and the formation of white rust due to

EPMA, or the like. the corrosion potential can be set to a potential almost equal to that of the MgZn phase

24

[0058]

20 The ratio of Zn to Al (Zn : Al) in the β phase is about 1 : 1, and the β phase

having excellent corrosion resistance can be present in this range. In addition, it is

preferable to satisfy the following Expression (4) at any point or in any region in the β

phase. By satisfying the following Expression (4), the electrical resistance of the β

phase is increased, and corrosion resistance can be further improved.

25 [0059]

The (Zn + Al) - (Cu + Ag) compound is a compound in which Cu, Ag, and Al 25

[0062]

0.85 ≤ [Al]/([Zn] + [Cu] + [Ag]) ≤ 1.15... (4) the potential of the plated layer can be increased.

Here, each of [Al], [Zn], [Cu], and [Ag] in Expression (4) is a quantitative small amount of a (Zn + Al) - (Cu + Ag) compound is finally present in the plated layer,

analysis value (at%) obtained by energy dispersive X-ray spectrometry in the β phase. diffusion plated layer disappears during hot-dip plating. However, in a case where a

(aggregate of Cu, Ag-Zn intermetallic compounds). However, the Cu-Ag-Zn-based

[0060] thermally diffused during pre-annealing to form a Cu-Ag-Zn-based diffusion plated layer

5original sheet by Furthermore, a method described the corrosion later. Zn, Cu, andcurrent Ag in thedensity pre-plateddepends layer are on the area fraction of the β

phase. Therefore, in any portion at the SEM cross section of the plated layer, the area it is preferable to provide Cu and/or Ag from a pre-plated layer formed on the plating

In order to appropriately supply Cu and/or Ag to the ß phase in the plated layer,

fraction of the β phase may be 3% or more. The area fraction of the β phase in the

[0061]

plated layer can be controlled by a manufacturing method. The area fraction of the β compound, an Al-Zn-Ag compound, and an Al-Zn-Cu-Ag compound.

phase is more preferably 5% or more, and still more preferably, the Cu + Ag intermetallic compound region containing at least one or more of an Al-Zn-Cu

Here, the term " phase" as described herein can also be said to be an

10 concentration in the plated layer is 0.4% or more, and the area fraction of the β phase is 10% or more.

10% or more. concentration in the plated layer is 0.4% or more, and the area fraction of the ß phase is

Here, the term “β phase” as described herein can also be said to be an phase is more preferably 5% or more, and still more preferably, the Cu + Ag

plated layer can be controlled by a manufacturing method. The area fraction of the ß

intermetallic compound region containing at least one or more of an Al-Zn-Cu fraction of the ß phase may be 3% or more. The area fraction of the ß phase in the

compound, an Al-Zn-Ag compound, and an Al-Zn-Cu-Ag compound. phase. Therefore, in any portion at the SEM cross section of the plated layer, the area

15 [0061] Furthermore, the corrosion current density depends on the area fraction of the ß

[0060]

In order to appropriately supply Cu and/or Ag to the β phase in the plated layer, analysis value (at%) obtained by energy dispersive X-ray spectrometry in the ß phase.

it Here, is preferable to provide each of [Al], [Zn], Cuinand/or

[Cu], and [Ag] Ag Expression (4) from a pre-plated layer formed on the plating is a quantitative

original sheet by a method described 0.85 [Al]/([Zn] + [Cu] + [Ag]) 1.15.. (4) later. Zn, Cu, and Ag in the pre-plated layer are 25

thermally diffused during pre-annealing to form a Cu-Ag-Zn-based diffusion plated layer

20 (aggregate of Cu, Ag-Zn intermetallic compounds). However, the Cu-Ag-Zn-based

diffusion plated layer disappears during hot-dip plating. However, in a case where a

small amount of a (Zn + Al) - (Cu + Ag) compound is finally present in the plated layer,

the potential of the plated layer can be increased.

[0062]

25 The (Zn + Al) - (Cu + Ag) compound is a compound in which Cu, Ag, and Al power of 30 W, an output voltage of 1000 V, and a discharge region in a circular region 26 sputtering, the analysis conditions include an argon pressure of 0.27 MPa, an output are slightly dissolved in Zn, and has a potential of -1.2 V(vs. Ag/AgCl in 1M NaCl). the depth direction, it is preferable to perform the analysis while performing Ar

Since the (Zn + Al) - (Cu + Ag) compound is thus allowed to remain in the final plated the measurement apparatus is not limited thereto. In a case of performing analysis in

layer, the potential of the plated layer can be further increased. inventors use LECO Japan 850A as the glow discharge optical emission spectrometer, but The (Zn + Al) - (Cu + a glow discharge optical emission spectrometer (GDS) may be used. The present

Ag) compound can be observed in the plated layer through SEM, and a quantitative As the analysis method for components in the plated layer in the depth direction,

5[0065] analysis value by point analysis can be determined in the same manner as described

above. Next, an example of an analysis method for the plated layer will be described.

[0064]

[0063] adhesion amount of the pre-plated layer.

In order to obtain the (Zn + Al) - (Cu + Ag) compound exhibiting an appropriate on the adhesion amount of Cu, Ag, and Zn on the original sheet, that is, depend on the

potential, the component ratio is preferably Zn + Al : Cu + Ag = 4 : 1 to 9 : 1. more per 10000 µm². The number of (Zn + Al) - (Cu + Ag) compounds tends to depend In plated layer, and the number thereof is preferably 10 or more, more preferably 20 or

10 addition, the (Zn + Al) - (Cu + Ag) compound has an equivalent circle diameter of 1 μm or more in any cross section among cross sections along the thickness direction of the

or more in any cross section among cross sections along the thickness direction of the addition, the (Zn + Al) - (Cu + Ag) compound has an equivalent circle diameter of 1 µm

plated layer, and the number thereof is preferably 10 or more, more preferably 20 or potential, the component ratio is preferably Zn + Al : Cu + Ag = 4 : 1 to 9 : 1. In

In order to obtain the (Zn + Al) - (Cu + Ag) compound exhibiting an appropriate

more per 10000 μm2. The number of (Zn + Al) - (Cu + Ag) compounds tends to depend

[0063]

above. on the adhesion amount of Cu, Ag, and Zn on the original sheet, that is, depend on the

15analysis adhesion amount of the pre-plated layer. value by point analysis can be determined in the same manner as described

Ag) compound can be observed in the plated layer through SEM, and a quantitative

[0064] layer, the potential of the plated layer can be further increased. The (Zn + Al) - (Cu +

Next, an example of an analysis method for the plated layer will be described. Since the (Zn + Al) - (Cu + Ag) compound is thus allowed to remain in the final plated

[0065] are slightly dissolved in Zn, and has a potential of -1.2 V(vs. Ag/AgCl in 1M NaCl).

26

As the analysis method for components in the plated layer in the depth direction,

20 a glow discharge optical emission spectrometer (GDS) may be used. The present

inventors use LECO Japan 850A as the glow discharge optical emission spectrometer, but

the measurement apparatus is not limited thereto. In a case of performing analysis in

the depth direction, it is preferable to perform the analysis while performing Ar

sputtering, the analysis conditions include an argon pressure of 0.27 MPa, an output

25 power of 30 W, an output voltage of 1000 V, and a discharge region in a circular region is specified, followed by specifying the field of view so that the component range of the 27 In a case where the area fraction of the ß phase is determined, the field of view having a diameter of 4 mm. The measurement is performed from the surface of the

[0067]

plated layer toward the depth direction until the Fe concentration reaches 100% (reaches identification and measurement of an area fraction of each phase are performed.

the base metal). Therefore, the analysis range of the depth direction analysis carried out selected fields of view are observed at magnifications of about 500 to 2000 times, and

observation samples are collected from one plated steel sheet, at least 30 randomly

by GDS is a range reaching from the plated surface to the Zn-Al-Mg plated layer, the of the field of view of the plated layer, in order to eliminate bias, at least three

5performed interfacial alloy layer after Au deposition on the(Al-Fe alloyoflayer), cross-section and the plated partForofthetheselection layer. steel material. After the GDS

analysis, the sputtering depth of the cross section is measured using surfcom130A observe the cross section of the plated layer. The cross-section observation may be

this sample is embedded in a resin. Next, the observed section is mirror-polished to

manufactured by Tokyo Seimitsu Co. Ltd. The elemental distribution profile of the out from a plated steel sheet such that a cross section of a plated layer is exposed, and

plated First, layer infortheobservation a sample depth direction is of having a size obtained about 20 Xby 20 the GDSis analysis. mm square cut In the elemental

distribution profile, in a case where the total amount of the detected elements is 100%, procedure.

The cross-section observation through SEM may be performed by the following

10 the distribution of the amount of each element in the depth direction is illustrated.

[0066]

[0066] the distribution of the amount of each element in the depth direction is illustrated.

The cross-section observation through SEM may be performed by the following distribution profile, in a case where the total amount of the detected elements is 100%,

plated layer in the depth direction is obtained by the GDS analysis. In the elemental

procedure. manufactured by Tokyo Seimitsu Co. Ltd. The elemental distribution profile of the

First, a sample for observation having a size of about 20 × 20 mm square is cut analysis, the sputtering depth of the cross section is measured using surfcom 130A

15interfacial outalloy from a plated steel sheet such that a cross section of a plated layer is exposed, and layer (Al-Fe alloy layer), and part of the steel material. After the GDS

by GDS is a range reaching from the plated surface to the Zn-Al-Mg plated layer, the

this sample is embedded in a resin. Next, the observed section is mirror-polished to the base metal). Therefore, the analysis range of the depth direction analysis carried out

observe the cross section of the plated layer. The cross-section observation may be plated layer toward the depth direction until the Fe concentration reaches 100% (reaches

performed after Au deposition on the cross-section of the plated layer. having a diameter of 4 mm. The measurement is performed from the surface of the For the selection 27

of the field of view of the plated layer, in order to eliminate bias, at least three

20 observation samples are collected from one plated steel sheet, at least 30 randomly

selected fields of view are observed at magnifications of about 500 to 2000 times, and

identification and measurement of an area fraction of each phase are performed.

[0067]

In a case where the area fraction of the β phase is determined, the field of view

25 is specified, followed by specifying the field of view so that the component range of the perform plating by directly adding Cu to a Zn-Al-Mg-based plating bath. However, in 28 As a method for forming the plated layer as described above, it is conceivable to β phase includes a region close to 0.85 ≤ [Al]/([Zn] + [Cu] + [Ag]) ≤ 1.15 by point

[0070]

analysis using EDS. In a case where the β phase has been found, a quantitative analysis be read as "Cu and Ag".

element mapping image of the entire plated layer is imaged. Ag. That is, the description regarding Cu described below may be read as "Ag", or may The same component and thus Cu will be described as a representative without distinguishing between Cu and

range is specified from Zn and Al of the imaged mapping image by using image analysis according to the present embodiment, Cu and Ag exhibit substantially the same behavior,

5according software “ImageJ”, to the present andwillbinarization embodiment orthe be described. In themanufacturing like is executed. method The area fraction of the β

phase in the plated layer is measured from the obtained binarized area. Next, a preferred method for manufacturing the hot-dip plated steel material

[Method for Manufacturing Hot-Dip Plated Steel Material]

[0068]

[0069]

In the same manner, Zn, Cu, and the equivalent circle diameter are measured for preferably observed from at least three samples.

the Zn-Cu compound. The distribution of the number of (Zn + Al) - (Cu + Ag) layer reaches 10000 µm². The number of (Zn + Al) - (Cu + Ag) compounds is

for each sample until the total area (corresponding to the number of pixels) of the plated

10 compounds can be determined by a function included in known image analysis software such as ImageJ. After observing each field of view, the number distribution is observed

such as ImageJ. After observing each field of view, the number distribution is observed compounds can be determined by a function included in known image analysis software

for each sample until the total area (corresponding to the number of pixels) of the plated the Zn-Cu compound. The distribution of the number of (Zn + Al) - (Cu + Ag)

In the same manner, Zn, Cu, and the equivalent circle diameter are measured for

layer reaches 10000 μm2. The number of (Zn + Al) - (Cu + Ag) compounds is

[0068]

preferably observed from at least three samples. phase in the plated layer is measured from the obtained binarized area.

15software

[0069] "ImageJ", and binarization or the like is executed. The area fraction of the ß

range is specified from Zn and Al of the imaged mapping image by using image analysis

[Method for Manufacturing Hot-Dip Plated Steel Material] element mapping image of the entire plated layer is imaged. The same component

Next, a preferred method for manufacturing the hot-dip plated steel material analysis using EDS. In a case where the ß phase has been found, a quantitative analysis

according to the present embodiment ß phase includes a region close to 0.85 will be described. In the manufacturing method

[Al]/([Zn] + [Cu] + [Ag]) 1.15 by point

28

according to the present embodiment, Cu and Ag exhibit substantially the same behavior,

20 and thus Cu will be described as a representative without distinguishing between Cu and

Ag. That is, the description regarding Cu described below may be read as “Ag”, or may

be read as “Cu and Ag”.

[0070]

As a method for forming the plated layer as described above, it is conceivable to

25 perform plating by directly adding Cu to a Zn-Al-Mg-based plating bath. However, in this order. Copper sulfate, copper cyanide, copper pyrophosphate, an alkanol bath, and 29 Therefore, it is preferable to form the pre-Zn-plated layer and the pre-Cu plated layer in this method, the formation of an intermetallic compound such as CuAl2 or a reaction may diffuse to the original sheet side, and a desired plated layer may not be obtained.

between base metal as a substrate and Cu occurs, so that there is a concern that Cu is not layer and the pre-Zn-plated layer are formed in this order, Cu in the pre-Cu plated layer

efficiently contained in the β phase. Therefore, as an example of a suitable procedure plated layer after forming the pre-Zn-plated layer. In a case where the pre-Cu plated

In the present embodiment, it is effective to form a pre-Cu plated layer on the pre-Zn-

for manufacturing the hot-dip plated steel material of the present embodiment, a method Thereafter, Cu is further plated on the Zn layer to form a pre-Cu plated layer.

5[0073] for supplying Cu from a pre-plated layer provided on a plating original sheet to a plated

layer will be described below as an example. zincate baths, zinc chloride baths, or zinc sulfate baths.

conventional zinc plating formation conditions, such as those using cyanide baths,

[0071] Zn plating on Fe is not particularly limited as long as it is performed under

[0072] First, Zn is plated in advance on a plating original sheet such as a cold-rolled

steel sheet or a hot-rolled steel sheet by electro plating to form a pre-Zn-plated layer plating, vapor deposition, or the like.

finally obtained plated layer. The plating means may be electro plating, substitution

10 (hereinafter, also simply referred to as a Zn-plated layer or a Zn layer). The adhesion amount of the Zn-plated layer is preferably equal to or more than the amount of Cu in the

amount of the Zn-plated layer is preferably equal to or more than the amount of Cu in the (hereinafter, also simply referred to as a Zn-plated layer or a Zn layer). The adhesion

finally obtained plated layer. The plating means may be electro plating, substitution steel sheet or a hot-rolled steel sheet by electro plating to form a pre-Zn-plated layer

First, Zn is plated in advance on a plating original sheet such as a cold-rolled

plating, vapor deposition, or the like.

[0071]

[0072] layer will be described below as an example.

15for supplying Cu fromZn plating on Fe is not particularly limited as long as it is performed under a pre-plated layer provided on a plating original sheet to a plated

for manufacturing the hot-dip plated steel material of the present embodiment, a method

conventional zinc plating formation conditions, such as those using cyanide baths, efficiently contained in the ß phase. Therefore, as an example of a suitable procedure

zincate baths, zinc chloride baths, or zinc sulfate baths. between base metal as a substrate and Cu occurs, so that there is a concern that Cu is not

[0073] this method, the formation of an intermetallic compound such as CuAl or a reaction

29

Thereafter, Cu is further plated on the Zn layer to form a pre-Cu plated layer.

20 In the present embodiment, it is effective to form a pre-Cu plated layer on the pre-Zn-

plated layer after forming the pre-Zn-plated layer. In a case where the pre-Cu plated

layer and the pre-Zn-plated layer are formed in this order, Cu in the pre-Cu plated layer

may diffuse to the original sheet side, and a desired plated layer may not be obtained.

Therefore, it is preferable to form the pre-Zn-plated layer and the pre-Cu plated layer in

25 this order. Copper sulfate, copper cyanide, copper pyrophosphate, an alkanol bath, and

450°C or higher. The temperature is more preferably 470°C or higher, still more 30 layer as the bath temperature is higher. Therefore, the bath temperature is preferably

the like can be applied to the Cu plating, and the plating bath is not particularly limited. more likely to be dissolved, and Cu is more likely to be finely dispersed in the plated

Silver cyanide can be used for Ag plating, and furthermore, Cu can be electroless plated. immersed in a Zn-Al-Mg-based plating bath and pulled up, the Zn-Cu-plated layer is

[0074] case where the original sheet on which the Zn-Cu diffusion-plated layer is formed is

temperature of the Zn-Al-Mg-based plating bath is preferably 450°C to 600°C. In a

In order to increase the number of (Zn + Al) - (Cu + Ag) compounds, it is immersed in a Zn-Al-Mg-based plating bath, and then pulled up. At this time, the bath

5 preferable thatsheet Next, the original theonadhesion amount which the Zn-Cu of thelayer diffusion-plated pre-Cu plated is formed is layer is more than 1/1000 of the

[0076] final plating adhesion amount. is preferably 450°C to 600°C.

[0075] and Zn may occur, which is not preferable. The temperature range of the pre-annealing

Then, the plating original sheet is heated to 450°C to 600°C. evaporation of the pre-Zn-plated layer and the formation of a reaction layer between Fe The heating may

also serve as annealing of the original sheet (hereinafter, the heating may be referred to as On the other hand, in a case where a heating temperature is higher than 600°C,

temperature is lower than 450°C, Cu may not be efficiently diffused into the plated layer.

10 pre-annealing). By the heating, Zn is dissolved and reacts with Cu to form an alloy, so that a Zn-Cu diffusion-plated layer can be formed. In a case where the heating

that a Zn-Cu diffusion-plated layer can be formed. pre-annealing). By the heating, Zn is dissolved and reacts with Cu to form an alloy, so In a case where the heating

temperature is lower than 450°C, Cu may not be efficiently diffused into the plated layer. also serve as annealing of the original sheet (hereinafter, the heating may be referred to as

Then, the plating original sheet is heated to 450°C to 600°C. The heating may

On the other hand, in a case where a heating temperature is higher than 600°C,

[0075]

evaporation of the pre-Zn-plated layer and the formation of a reaction layer between Fe final plating adhesion amount.

15preferable andthat Zn the may occur, which is not preferable. The temperature range of the pre-annealing adhesion amount of the pre-Cu plated layer is more than 1/1000 of the

In order to increase the number of (Zn + Al) - (Cu + Ag) compounds, it is

is preferably 450°C to 600°C.

[0074]

[0076] Silver cyanide can be used for Ag plating, and furthermore, Cu can be electroless plated.

Next, the original sheet on which the Zn-Cu diffusion-plated layer is formed is the like can be applied to the Cu plating, and the plating bath is not particularly limited.

30

immersed in a Zn-Al-Mg-based plating bath, and then pulled up. At this time, the bath

20 temperature of the Zn-Al-Mg-based plating bath is preferably 450°C to 600°C. In a

case where the original sheet on which the Zn-Cu diffusion-plated layer is formed is

immersed in a Zn-Al-Mg-based plating bath and pulled up, the Zn-Cu-plated layer is

more likely to be dissolved, and Cu is more likely to be finely dispersed in the plated

layer as the bath temperature is higher. Therefore, the bath temperature is preferably

25 450°C or higher. The temperature is more preferably 470°C or higher, still more

CAZmax/CAZmin may increase. Therefore, the average cooling rate in the temperature 31 Zn-Cu cannot be sufficiently incorporated into the ß phase, and as a result,

preferably 500°C or higher, and even still more preferably 550°C or higher. On the 450°C is too high, the amount of the ß phase cannot be sufficiently secured. Therefore,

other hand, in a case where the bath temperature is excessively high, Zn in the plating In addition, in a case where the average cooling rate in the temperature range of 550°C to

bath is evaporated, and the bath balance is easily lost. Therefore, the bath temperature range of 550°C to 450°C, the subsequent formation of the ß phase may be insufficient.

be inhibited. In a case where the phase is not sufficiently grown in the temperature

is preferably 600°C or lower. The bath temperature is more preferably 580°C or lower. cooling rate in this temperature range is higher than 10°C, the growth of the phase may

5the In the present embodiment, temperature control is preferably performed when phase is formed and the ß phase is not formed. In a case where the average

theTheplating original sheet is pulled up. That is, by performing appropriate temperature temperature range of 550°C to 450°C is a temperature range in which only

[0078]

control and cooling control after immersion, Cu is finely dispersed in the plating bath, Al () phase, a large amount of Zn-Cu fine compounds can remain.

and Cu is contained in the Zn-Al (β) phase in the solidification process of the plated fine compounds incorporated from the plating original sheet are not dissolved in the solid

layer. (ß phase) precipitates and grows so as to surround the Al () phase. Since the Zn-Cu

grown from the plating molten state. After the Al () phase is sufficiently grown, Zn-Al

10 [0077] The Zn-Al (ß) phase is a phase formed after the Al () phase is precipitated and

[0077] The Zn-Al (β) phase is a phase formed after the Al (α) phase is precipitated and layer. grown from the plating molten state. After the Al (α) phase is sufficiently grown, Zn-Al and Cu is contained in the Zn-Al (ß) phase in the solidification process of the plated

(β phase) precipitates and grows so as to surround the Al (α) phase. Since the Zn-Cu control and cooling control after immersion, Cu is finely dispersed in the plating bath,

fine compounds incorporated from the plating original sheet are not dissolved in the solid the plating original sheet is pulled up. That is, by performing appropriate temperature

15 AlIn(α) phase, a large amount of Zn-Cu fine compounds can remain. the present embodiment, temperature control is preferably performed when

is preferably 600°C or lower. The bath temperature is more preferably 580°C or lower.

[0078] bath is evaporated, and the bath balance is easily lost. Therefore, the bath temperature

The temperature range of 550°C to 450°C is a temperature range in which only other hand, in a case where the bath temperature is excessively high, Zn in the plating

the α phase is formed and the β phase is not formed. Inthe a case where the average preferably 500°C or higher, and even still more preferably 550°C or higher. On

31

cooling rate in this temperature range is higher than 10°C, the growth of the α phase may

20 be inhibited. In a case where the α phase is not sufficiently grown in the temperature

range of 550°C to 450°C, the subsequent formation of the β phase may be insufficient.

In addition, in a case where the average cooling rate in the temperature range of 550°C to

450°C is too high, the amount of the β phase cannot be sufficiently secured. Therefore,

Zn-Cu cannot be sufficiently incorporated into the β phase, and as a result,

25 CAZmax/CAZmin may increase. Therefore, the average cooling rate in the temperature corrosion potential immediately after immersion shifts markedly to the negative side, but 32 sufficiently washed and the steel sheet is then immersed in the measurement solution, the range of 550°C to 450°C is set to 10°C/sec or lower. and constant room temperature. In a case where the plated steel sheet surface is

[0079] measurement solution, the method being carried out under conditions such as degassing

The average cooling rate in the temperature range of 450°C to 350°C is not reference electrode is used and 1 M NaCl aqueous solution is employed as a

Examples of the evaluation method include a method in which an Ag/AgCl-type

particularly limited. However, in a case where the average cooling rate between 450°C electrode, a salt bridge, or a potentiostat (constant potential electric field device).

5general and device350°C is low, configuration using athe β phase device such as anamount cancell, electrochemical be increased. a reference Therefore, the average cooling

rate between 450°C and 350°C is preferably 8°C/sec or lower. The corrosion potential and the like of the plated layer can be measured by a

(Corrosion Potential)

[0080]

[0082]

will be described. The average cooling rate in the temperature range of lower than 350°C does not

affect the formation of the β phase. The cooling condition in the temperature range of Next, a method for evaluating performance of the hot-dip plated steel material

[0081]

10 lower than 350°C is not particularly limited because it does not affect the potential, the corrosion current density, and the like.

corrosion current density, and the like. lower than 350°C is not particularly limited because it does not affect the potential, the

[0081] affect the formation of the ß phase. The cooling condition in the temperature range of

The average cooling rate in the temperature range of lower than 350°C does not

Next, a method for evaluating performance of the hot-dip plated steel material

[0080]

will be described. rate between 450°C and 350°C is preferably 8°C/sec or lower.

15and 350°C

[0082] is low, the ß phase amount can be increased. Therefore, the average cooling

particularly limited. However, in a case where the average cooling rate between 450°C

(Corrosion Potential) The average cooling rate in the temperature range of 450°C to 350°C is not

[0079] The corrosion potential and the like of the plated layer can be measured by a

general device configuration using a device such as an electrochemical cell, a reference range of 550°C to 450°C is set to 10°C/sec or lower.

32

electrode, a salt bridge, or a potentiostat (constant potential electric field device).

20 Examples of the evaluation method include a method in which an Ag/AgCl-type

reference electrode is used and 1 M NaCl aqueous solution is employed as a

measurement solution, the method being carried out under conditions such as degassing

and constant room temperature. In a case where the plated steel sheet surface is

sufficiently washed and the steel sheet is then immersed in the measurement solution, the

25 corrosion potential immediately after immersion shifts markedly to the negative side, but polarization curve, and the corrosion potential is determined by the Tafel extrapolation 33 The potential is varied in both the positive and negative directions to obtain a in a case where the steel sheet is immersed in the solution for about 1800 seconds, the (Corrosion Current Density)

[0085] potential is stabilized. This potential is the corrosion potential of the surface of the

plated layer. the evaluation surface of the corrosion test was "less than 10%".

A: The corrosion potential was -1.2 to -1.1V, and the white rust area fraction on

[0083] the evaluation surface of the corrosion test was "10% to 15% or more".

5 In a case where the corrosion potential approaches -1.1 V, the variation in B: The corrosion potential was -1.25 to -1.2V, and the white rust area fraction on

potential of the plated layer is reduced, which is preferable, and the amount of white rust the evaluation surface of the corrosion test was "15% to 20% or more".

C: The corrosion potential was -1.25 to -1.2V, and the white rust area fraction on

formed at the initial stage of corrosion can be minimized. The initial stage of corrosion on the evaluation surface of the corrosion test was "20% to 25% or more".

refers D: The to a tendency corrosion of-1.3 potential was a white to -1.25 rust V, andarea fraction the white rust areaafter 24 hours of a salt spray test (SST) fraction

as specified in JIS Z 2371 (2015). the evaluation surface of the corrosion test is "25% or more".

E: The corrosion potential is -1.3 V or less, and the white rust area fraction on

10 [0084] <Evaluation Criteria>

[0084] <Evaluation Criteria>

E: The corrosion potential is -1.3 V or less, and the white rust area fraction on as specified in JIS Z 2371 (2015).

refers to a tendency of a white rust area fraction after 24 hours of a salt spray test (SST)

the evaluation surface of the corrosion test is “25% or more”. formed at the initial stage of corrosion can be minimized. The initial stage of corrosion

D: The corrosion potential was -1.3 to -1.25 V, and the white rust area fraction potential of the plated layer is reduced, which is preferable, and the amount of white rust

15 onInthe evaluation surface of the corrosion test was “20% to 25% or more”. a case where the corrosion potential approaches - -1.1 V, the variation in

[0083]

C: The corrosion potential was -1.25 to -1.2V, and the white rust area fraction on plated layer.

the evaluation surface of the corrosion test was “15% to 20% or more”. potential is stabilized. This potential is the corrosion potential of the surface of the

B: The corrosion potential was -1.25 to -1.2V, and the white rust area fraction on in a case where the steel sheet is immersed in the solution for about 1800 seconds, the

33

the evaluation surface of the corrosion test was “10% to 15% or more”.

20 A: The corrosion potential was -1.2 to -1.1V, and the white rust area fraction on

the evaluation surface of the corrosion test was “less than 10%”.

[0085]

(Corrosion Current Density)

The potential is varied in both the positive and negative directions to obtain a

25 polarization curve, and the corrosion potential is determined by the Tafel extrapolation

In the hot-dip plated steel material of the present embodiment, a film may be 34

[0088]

method. The corrosion current density depends on the corrosion rate. This can also be coating treatments may be performed.

inferred After thefrom plated the corrosion layer weightchemical is formed, various loss in the salttreatments conversion spray test. and That is, since only the β

[0087] phase corrodes at the initial stage, the corrosion weight loss after 120 hours of the SST is (A/cm²) is less than -6 and the corrosion weight loss is less than 5g/m². measured. In the method for measuring the corrosion weight loss, the corrosion amount S: A case where the measured value of the corrosion current density log |i|

5(A/cm²) of the β phase can be estimated by immersing the steel sheet before and after the is -6 to -5.5 and the corrosion weight loss is 5g/m² or more.

corrosion test in 30% chromic acid for 5 minutes. A: A case where the measured value of the corrosion current density log |i|

(A/cm²) is -5.5 to -5 and the corrosion weight loss is 10g/m² or more.

[0086] B: A case where the measured value of the corrosion current density log |i|

<Evaluation Criteria> -4.5, and the corrosion weight loss is 15 g/m² or more.

E: A case where the measured value of the corrosion current density log |i| C: The value obtained when the corrosion current density log |i| (A/cm²) is -5 to

(A/cm²) is -4.5 to -4 and the corrosion weight loss is 20g/m² or more.

10 (A/cm2) is -4 or more and the corrosion weight loss is 25g/m2 or more. D: A case where the measured value of the corrosion current density log |i|

D: A case where the measured value of the corrosion current density log |i| (A/cm²) is -4 or more and the corrosion weight loss is 25g/m² or more.

2 where the measured value of the corrosion current density log |i| (A/cm ) is -4.5 to -4 and the corrosion weight loss is 20g/m2 or more. E: A case

C: The value obtained when the corrosion current density log |i| (A/cm2) is -5 to

[0086]

-4.5, and the corrosion weight loss is 15 g/m2 or more. corrosion test in 30% chromic acid for 5 minutes.

15of the ß phase can beB: A case where the measured value of the corrosion current density log |i| estimated by immersing the steel sheet before and after the

measured. In the method for measuring the corrosion weight loss, the corrosion amount

(A/cm2) is -5.5 to -5 and the corrosion weight loss is 10g/m2 or more. phase corrodes at the initial stage, the corrosion weight loss after 120 hours of the SST is

A: A case where the measured value of the corrosion current density log |i| inferred from the corrosion weight loss in the salt spray test. That is, since only the ß

2 2 (A/cm ) is -6 to -5.5 and the corrosion weight loss is 5g/m or more. method. The corrosion current density depends on the corrosion rate. This can also be

34

S: A case where the measured value of the corrosion current density log |i|

20 (A/cm2) is less than -6 and the corrosion weight loss is less than 5g/m2.

[0087]

After the plated layer is formed, various chemical conversion treatments and

coating treatments may be performed.

[0088]

25 In the hot-dip plated steel material of the present embodiment, a film may be electrolysis, a reaction type chromate-free treatment in which a film is formed by 35 electrolytic chromate-free treatment in which a chromate-free film is formed by formed on the plated layer. A film having a single layer or two or more layers may be environment is particularly suitable. The chromate-free treatment includes an formed. Examples The chromate-free ofwhich treatment the type ofimpose does not the film immediately a burden on the above the plated layer include a

[0092] chromate film, a phosphate film, and a chromate-free film. A chromate treatment, a zinc calcium phosphate treatment, and a manganese phosphate treatment.

phosphating treatment, and a chromate-free treatment for forming these films can be Examples of the phosphating treatment include a zinc phosphate treatment, a

5[0091] performed by known methods.

[0089] a diisopropanolamine-modified epoxy resin, and the like), and hard silica.

vinyl ester resin, a vinyl acetate acrylic emulsion, a carboxylated styrene-butadiene latex,

The chromate treatment includes an electrolytic chromate treatment in which a treatment using chromic acid, a silica sol, a resin (phosphoric acid, an acrylic resin, a

chromate Examples offilm is formedchromate the electrolytic by electrolysis, a reaction treatment include type chromate an electrolytic chromate treatment in which a

[0090] film is formed by utilizing a reaction with the material and then the excess treatment liquid without washing with water. Any treatment may be adopted.

10 liquid is washed away, and an application type chromate treatment in which a film is formed by applying a treatment liquid to an object to be coated and drying the treatment

formed by applying a treatment liquid to an object to be coated and drying the treatment liquid is washed away, and an application type chromate treatment in which a film is

liquid without washing with water. Any treatment may be adopted. film is formed by utilizing a reaction with the material and then the excess treatment

chromate film is formed by electrolysis, a reaction type chromate treatment in which a

[0090] The chromate treatment includes an electrolytic chromate treatment in which a

[0089] Examples of the electrolytic chromate treatment include an electrolytic chromate performed by known methods. 15 treatment using chromic acid, a silica sol, a resin (phosphoric acid, an acrylic resin, a

phosphating treatment, and a chromate-free treatment for forming these films can be

vinyl ester resin, a vinyl acetate acrylic emulsion, a carboxylated styrene-butadiene latex, chromate film, a phosphate film, and a chromate-free film. A chromate treatment, a

a diisopropanolamine-modified epoxy resin, and the like), and hard silica. formed. Examples of the type of the film immediately above the plated layer include a

[0091] formed on the plated layer. A film having a single layer or two or more layers may be

35

Examples of the phosphating treatment include a zinc phosphate treatment, a

20 zinc calcium phosphate treatment, and a manganese phosphate treatment.

[0092]

The chromate-free treatment which does not impose a burden on the

environment is particularly suitable. The chromate-free treatment includes an

electrolytic chromate-free treatment in which a chromate-free film is formed by

25 electrolysis, a reaction type chromate-free treatment in which a film is formed by present invention, and the present invention is not limited to these examples of 36 Examples are examples of conditions adopted to confirm feasibility and an effect of the utilizing a reaction with the material and then the excess treatment liquid is washed away, Next, Examples of the present invention will be described, but conditions in

[0095] and an application type chromate-free treatment in which a film is formed by applying a Examples treatment liquid to an object to be coated and drying the treatment liquid without washing dissolved or dispersed in water may be used.

with water. Any treatment may be adopted. coloring pigment or antirust pigment. Also, water-based organic resins which are

5other organic

[0093]resin may be mixed and used. The organic resin film may contain any

Further, an organic resin film made of a single layer or two or more layers may by modifying, in the presence of at least one type of organic resin, at least one type of

organic resins) may be mixed and used, or one or more types of organic resins obtained

be formed on the film immediately above the plated layer. The organic resin is not As such an organic resin, one or more types of organic resins (unmodified

[0094] limited to a specific type, and examples thereof include polyester resins, polyurethane

resins, epoxy resins, acrylic resins, polyolefin resins, and modified products of these reacting with the functional group in the structure thereof.

(a monomer, a crosslinking agent, or the like) having a functional group capable of

10 resins. Here, the modified product refers to a resin obtained by causing a reactive functional group included in the structures of these resins to react with another compound

functional group included in the structures of these resins to react with another compound resins. Here, the modified product refers to a resin obtained by causing a reactive

(a monomer, a crosslinking agent, or the like) having a functional group capable of resins, epoxy resins, acrylic resins, polyolefin resins, and modified products of these

limited to a specific type, and examples thereof include polyester resins, polyurethane

reacting with the functional group in the structure thereof. be formed on the film immediately above the plated layer. The organic resin is not

[0094] Further, an organic resin film made of a single layer or two or more layers may

15[0093] As such an organic resin, one or more types of organic resins (unmodified

with water. Any treatment may be adopted.

organic resins) may be mixed and used, or one or more types of organic resins obtained treatment liquid to an object to be coated and drying the treatment liquid without washing

by modifying, in the presence of at least one type of organic resin, at least one type of and an application type chromate-free treatment in which a film is formed by applying a

other organic resin may be mixed and used. The organic resin film may contain any utilizing a reaction with the material and then the excess treatment liquid is washed away,

36

coloring pigment or antirust pigment. Also, water-based organic resins which are

20 dissolved or dispersed in water may be used.

Examples

[0095]

Next, Examples of the present invention will be described, but conditions in

Examples are examples of conditions adopted to confirm feasibility and an effect of the

25 present invention, and the present invention is not limited to these examples of

Silver plating conditions: KAg (CN) 2 of 40 g/L (in terms of Ag), KPO of 150 37

[0100]

conditions. The present invention may adopt various conditions as long as an object of anode made of oxygen-free high-purity copper, a current density of 3 A/dm².

the present invention is achieved without departing from the gist of the present invention. pyrophosphate of 290 g/L, ammonia water of 3 mg/L, potassium nitrate of 10 g/L, an

[0096] Copper plating conditions: copper pyrophosphate of 80 g/L, potassium

[0099]

First, a cold-rolled steel sheet (corresponding to SPCC specified in JIS G 3141 silver plating bath was adjusted by H4P2O7 and KOH.

5copper plating (2017)) bath having a size was subjected to air of 100 Inmm stirring. × 200 addition, the mm and pH of the a sheet thickness of 0.8 mm was following

prepared as a plating original sheet. For this cold-rolled steel sheet, first, a Zn-plated immersed in a copper plating bath and a silver plating bath in this order. The following

of forming the plated layer containing Cu and Ag, the plating original sheet was

layer was formed by depositing a predetermined amount of Zn onto the sheet surface using the following copper plating bath and the following silver plating bath. In a case

using a zinc plating bath described below. Ag was formed on the plating original sheet on which the Zn-plated layer was formed,

[0097] Next, a Cu-plated layer or Ag-plated layer, or a plated layer containing Cu and

[0098]

10 Zinc plating conditions: a zinc chloride of 50 g/L, an ammonium chloride of 200 g/L, pH = 5.5, a bath temperature of 30°C, a current density of 2 A/dm².

g/L, ZincpH = 5.5, plating a batha temperature conditions: zinc chloride ofof 50 30°C, a current g/L, an ammonium density chloride of 2 A/dm2. of 200

[0097]

[0098] using a zinc plating bath described below.

Next, a Cu-plated layer or Ag-plated layer, or a plated layer containing Cu and layer was formed by depositing a predetermined amount of Zn onto the sheet surface

Ag was formed on the plating original sheet on which the Zn-plated layer was formed, prepared as a plating original sheet. For this cold-rolled steel sheet, first, a Zn-plated

15(2017))using the following copper plating bath and the following silver plating bath. In a case having a size of 100 mm X 200 mm and a sheet thickness of 0.8 mm was

First, a cold-rolled steel sheet (corresponding to SPCC specified in JIS G 3141

[0096]

immersed in a copper plating bath and a silver plating bath in this order. the present invention is achieved without departing from the gist of the present invention. The following

copper plating bath was subjected to air stirring. In addition, the pH of the following conditions. The present invention may adopt various conditions as long as an object of

37

silver plating bath was adjusted by H4P2O7 and KOH.

20 [0099]

Copper plating conditions: copper pyrophosphate of 80 g/L, potassium

pyrophosphate of 290 g/L, ammonia water of 3 mg/L, potassium nitrate of 10 g/L, an

anode made of oxygen-free high-purity copper, a current density of 3 A/dm2.

[0100]

25 Silver plating conditions: KAg (CN) 2 of 40 g/L (in terms of Ag), K4P2O7 of 150 cooling rate illustrated in Tables 1A to 1C. 38 free and nitrogen-replaced atmosphere was then blown and air-cooled at the average g/L, EDTA (4 potassium salt) of 5 g/L, a smooth material HS II (* Selenium and 140 g/m² with N wiping gas, and N gas whose flow rate was controlled in an oxygen- mercapto Immediatelycompounds) ofup,0.5 after the pulling themL/L, adhesionpH=8 to 9, amount was a current adjusted to 135 density to of 40 A/dm2, a bath temperature of 40°C, an anode of Pt/Ti electrode. was then pulled up at 600 mm/sec.

immersion rate of 600 mm/sec, stopped in the bath for 3 seconds, and the plated substrate

[0101] bath temperature was set to 550°C to 600°C, the plated substrate was immersed at an

5is heated to a predetermined After thetemperature Cu-plated in alayer H (25%)or -NAg-plated layer, atmosphere. The or the plated layer containing Cu plating

and Ag was formed on the plating original sheet, the plating original sheet was heated at history until the completion of plating solidification was grasped. The plated steel sheet

original sheet was bonded to a K thermocouple by spot welding, and the temperature

the pre-annealing temperature illustrated in Tables 1A to 1C for 0.5 to 3 minutes to form Next, one point (the center rear surface of the evaluation surface) of the plating

a diffusion-plated layer, thereby obtaining a plated substrate. oxygen-free and nitrogen-substituted atmosphere (O concentration: less than 5 ppm). The composition of the

diffusion-plated layer is illustrated in Tables 1A to 1C. prepared by a vacuum dissolution method, and a plating bath was formed in a completely

First, alloys having plating bath components illustrated in Tables 1A to 1C were

10 [0102] The resulting plated substrate was hot-dip plated in a hot-dip plating simulator.

[0102] The resulting plated substrate was hot-dip plated in a hot-dip plating simulator.

First, alloys having plating bath components illustrated in Tables 1A to 1C were diffusion-plated layer is illustrated in Tables 1A to 1C.

a diffusion-plated layer, thereby obtaining a plated substrate. The composition of the

prepared by a vacuum dissolution method, and a plating bath was formed in a completely the pre-annealing temperature illustrated in Tables 1A to 1C for 0.5 to 3 minutes to form

oxygen-free and nitrogen-substituted atmosphere (O concentration: less than 5 ppm). and Ag was formed on the plating original sheet, the plating original sheet was heated 2 at

15 Next, one point (the center rear surface of the evaluation surface) of the plating After the Cu-plated layer or Ag-plated layer, or the plated layer containing Cu

[0101]

original sheet was bonded to a K thermocouple by spot welding, and the temperature temperature of 40°C, an anode of Pt/Ti electrode.

history until the completion of plating solidification was grasped. mercapto compounds) of 0.5 mL/L, pH=8 to 9, a current density of 40 A/dm², a bath The plated steel sheet

is heated to a predetermined temperature in a H2 (25%) -N2 atmosphere. g/L, EDTA (4 potassium salt) of 5 g/L, a smooth material HS II (* Selenium and The plating 38

bath temperature was set to 550°C to 600°C, the plated substrate was immersed at an

20 immersion rate of 600 mm/sec, stopped in the bath for 3 seconds, and the plated substrate

was then pulled up at 600 mm/sec.

Immediately after the pulling up, the adhesion amount was adjusted to 135 to

140 g/m2 with N2 wiping gas, and N2 gas whose flow rate was controlled in an oxygen-

free and nitrogen-replaced atmosphere was then blown and air-cooled at the average

25 cooling rate illustrated in Tables 1A to 1C.

A plated steel sheet was obtained by the above-described steps.

[0103]

Next, samples for evaluation were cut out from the various plated steel sheets.

Each sample for GDS analysis and SEM observation was cut out at a 30 mm square

[0105]

510000 µm² position on the opposite side to the thermocouple position. As the sample for corrosion, in any cross section along the thickness direction of the plated layer.

100 × 50 mm was taken from the center portion of the plated steel sheet. + Al) - (Cu + Ag) compounds having an equivalent circle diameter of 1 µm or more per

value is not preferable. In addition, (*) in Tables 2A to 2C indicates the number of (Zn

[0104] present invention or out of the preferable manufacturing conditions, or the characteristic

As the evaluation of the various samples that have been cut, an electrochemical the underline in each table indicates that the numerical value is out of the range of the

test and a corrosion test SST were performed. Among the compositions of the plated layer, the GDS analysis results, and each configuration in the ß phase region. Note that

Tables 2A to 2C show the evaluation results, the compositions of the plated

10 layer, the composition of Fe was not described in the tables, but was in a range of 0% to 5%.

5%. layer, the composition of Fe was not described in the tables, but was in a range of 0% to

Tables 2A to 2C show the evaluation results, the compositions of the plated test and a corrosion test SST were performed. Among the compositions of the plated

As the evaluation of the various samples that have been cut, an electrochemical

layer, the GDS analysis results, and each configuration in the β phase region. Note that

[0104]

the underline in each table indicates that the numerical value is out of the range of the 100 X 50 mm was taken from the center portion of the plated steel sheet.

15positionpresent invention or out of the preferable manufacturing conditions, or the characteristic on the opposite side to the thermocouple position. As the sample for corrosion,

Each sample for GDS analysis and SEM observation was cut out at a 30 mm square

value is not preferable. In addition, (*) in Tables 2A to 2C indicates the number of (Zn Next, samples for evaluation were cut out from the various plated steel sheets.

[0103] + Al) - (Cu + Ag) compounds having an equivalent circle diameter of 1 μm or more per

10000 μm2 insheet A plated steel anywas cross section along the thickness direction of the plated layer. obtained by the above-described steps.

39

[0105]

La = 0.1 Ce =

Cr = 0.5%

Ce = 0.1 La = 0.1 La = 0.1 Bi = 0.1 Sn = 0.1 Others V = 0.1 Y 0.1

0.1

[Table 1A] Cu + Ag

(mass%) component bath Plating (mass%) component bath Plating 0 0 0 0 0 0 0 0 Manufacturing method 0 0 0 0 0 0 0 0 0 0 0 0 Ag Pre-annealing Average cooling rate Diffusion-plated layer No. Type temperature 0 0 0 0 0 0 0 0 Bath 0 0 0 0 0 0 Plating bath component 0 0 0(mass%)0 0 0 (°C/sec) (mass%) (°C) Cu temperature 550- 450- 0 0 0 Zn Cu 0.01Ag0.01 Σ 0 0 0 0 (°C) 0 Zn0 Al0 0 0.01 Mg 0 Ca 0 0Si 0 Cu0 0Ag 0Cu + Ag0 0.01 Others 00.01 450°C 350°C0.2 0.2 0.2 0.3 0.5 0.5 0.5 0.1 0.1 0.2 0.2 Si Comparative 0 0 1 600 5 5 0.2 0.8 0.2 0.27 0.2 0.270 0.54 550 85.6 10.0 4.0 0.2 0.2 0 0 00 0 0.2 0.2 0.2 0.1 Example Ca 2 Example 500 10 6 4.0 0.8 5.0 0.27 5.0 5.0 0 00.2700 0.54 5.0 5.0 0 550 5.0 0 83.60 11.0 5.0 0.20 0.2 0 00 00 0 0 0 5.0 6.0 7.0 7.0 7.0 5.0 7.0 5.0 6.0 6.0 5.0 5.0 0 5.0 Manufacturing method

Mg 3 Example 500 10 6 0.8 0 0.300 0.30 550 83.6 11.0 5.0 0.2 0.2 0 0 0 10.0 11.0 11.0 12.0 12.0 12.0 12.0 12.0 12.0 12.0 12.0 12.0 15.0 15.0 19.0 19.0 19.0 12.0 12.0 12.0 4 Example 550 10 Al 8 0.8 0.27 0.000 0.27 550 82.99 12.0 5.0 0 0.01 0 0 0 Ce = 0.1 82.99 82.99 82.99 79.99 82.99 Example 580 10 8 85.6 0.883.6 83.6 0.27 0.000 0.27 550 81.7 82.99 12.0 80.3 5.0 80.3 80.3 0 77.8 0.01 75.9 074.8 74.80 0 La = 0.1 Zn 83 83 83 83 Comparative temperature 6 590 12 10 0.8 0.27 0.000 0.27 550 83 12.0 5.0 0 0 0 0 0 Example Bath (°C) 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 Comparative 7 550 12 4 0.8 0.27 0.000 0.27 550 83 12.0 5.0 0 0 0 0 0 Example 40

8 Example 550 3 11 0.54 0.30 0.8 0.54 0.27 0.27 0.27 0.000 0.27 0.27 0.27 550 0.27 0.51 82.99 1.36 12.0 1.35 5.0 1.35 00.27 0.54 0.01 0.14 00.40 0.27 0 0.40 0 0.27 La0.27 = 0.1 layer Diffusion-plated layer Diffusion-plated La = 0.1 Ce = 9 Example 480 10 8 0.270 1.2 0.270 0.300 0.405 0.000 0.100 0.000 0.51 0.000 0.000 550 0.000 81.7 0.100 0.680 12.0 0.670 6.0 0.670 0.135 0 0.000 0.3 0.000 0.130 0 0.000 0 0.130 0 0.000 0.000 (mass%) 0.1 Ag 10 Example 470 9 9 2.0 0.675 0.680 1.36 550 80.3 0.405 12.0 0.675 7.0 0.675 0.2 0.675 0.5 0.135 0.135 0 0 0 Bi = 0.1 0.27 0.27 0.27 0.27 0.27 0.27 0.27 0.54 0.27 0.27 0.27 0.27 0.27 11 Example 450 8 Cu 2 2.0 0.675 0.670 1.35 550 80.3 12.0 7.0 0.2 0.5 0 0 0 12 Example 460 1 11 0.8 0.8 2.0 0.8 0.675 0 0.8 0.670 0.8 0.8 1.35 0.8 550 0.8 80.31.2 2.0 12.0 2.0 0.4 7.0 2.0 0.2 1.6 0.5 0.4 00.8 0.80 0.8 0 0.8 0.8 Zn Average cooling rate

13 Example 550 10 2 350°C 0.4 0.135 0.135 0.27 550 79.99 15.0 5.0 0 0.01 0 0 0 Sn = 0.1 450- (°C/sec) 10 10 14 Example 550 10 8 1.6 0.54 0.000 0.54 550 11 77.8 15.0 7.0 11 0.1 0.1 10 0 0 50 0 15 Example 550 8 10 5 6 6 8 8 0.4 0.135 0.000 0.14 4550 75.9 8 9 2 19.0 5.0 0 0.1 2 8 4 4 0 0 0 5 V = 0.1 450°C 550- 16 Example 550 10 4 0.8 10 0.27 10 10 0.130 10 0.40 12 550 12 74.8 10 19.0 6.0 010 10 0.2 010 100 50 0 15 Y10= 0.1 Pre-annealing 17 Example 500 temperature 10 4 5 0.8 0.27 0.000 0.27 550 3 74.8 9 8 1 19.0 6.0 0 0.2 8 0 0 0 Cr = 0.5% Comparative (°C) 600 500 550 580 590 550 550 470 450 460 550 550 500 550 550 550 18 550 50 50 0.8 500 0.27 0.130 0.40 550 83480 12.0 5.0 0550 0 0550 0 0 Example Comparative Comparative Comparative Comparative Comparative Comparative 19 550 15 5 0.8 Example Example 0.27 Example 0.000 Example Example 0.27 Example 550 Example Example 83 Example 12.0 Example 5.0 Example Example 0 Example 0 Example Example 0 Example Example 0 Example 0 Example Example Example Type

[Table 1A] 20 Example 550 10 10 0.8 0.27 0.000 0.27 550 82.99 12.0 5.0 0 0.01 0 0 0

No. 10 11 12 13 14 15 16 17 18 19 20 1 2 3 4 5 6 7 8 9

Mo = 0.1 Mo = 0.1 Co = 0.1 Others B = 0.1 B 0.1

[0106] Cu+Ag

(mass%) component bath Plating (mass%) component bath Plating

[Table 1B] 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Ag 0 0 0 0 0 0 Manufacturing 0 0 0 0 0 0 0 0 0method Cu Pre-annealing 0 0 Average cooling rate Diffusion-plated 0 0 0 layer 0.3 0.1 0.1 0.1 0.1 0.1 0.1 0.2 0.1 0.3 0.2 0.2 0.7 0.7 0.1 0 0bath0component 0 (mass%) No. Type temperature 0Bath 0 0 0 0 0 Plating (°C/sec) Si (mass%) (°C) temperature 550- 450- 0.3 0.4 0.2 0.2(°C) 0.2 0.3 0.6 0.3 0.5 CaZn Cu0.4 Ag Σ0.2 Zn Al Mg0.6 Ca Si0.3 Cu Ag Cu+Ag Others 450°C 350°C 0 0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 12.0 21 Example 550 Manufacturing method 9 9 8.0 0.405 0.000 0.41 550 72.45.0 6.0 19.0 8.07.0 7.0 0.3 9.0 0.39.0 0 0 0 Mo = 0.1 Mg1.2 22 Example 550 5 5 3.2 19.0 1.0819.0 0.300 19.0 19.0 19.0 1.38 19.0550 19.0 70.520.0 19.0 20.0 25.010.030.0 30.0 0.4 30.0 0.130.0 0 30.0 0 0 B = 0.1 Al 23 Example 550 5 5 3.2 1.08 0.300 1.38 550 70.5 19.0 10.0 0.4 0.1 0 0 0 B = 0.1 72.4 70.5 70.7 70.7 70.7 70.7 73.9 64.4 62.2 62.2 57.4 24 Example 550 10 8 Zn4.1 1.3570.5 0.000 1.35 550 70.774.8 19.0 10.0 0.2 60 0.160 0 0 0 temperature 25 Example 550 10 8 4.1 1.35 0.000 1.35 550 70.7 19.0 10.0 0.2 0.1 0 0 0 Mo = 0.1 Bath (°C) Comparative 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 26 550 12 12 4.1 1.35 0.000 1.35 550 70.7 19.0 10.0 0.2 0.1 0 0 0 Example 41

Comparative 0.41 1.38 1.35 1.35 1.35 2.03 2.70 4.05 5.00 4.73 5.40 27 550 12 layer Diffusion-plated layer Diffusion-plated 8 4.1 1.351.38 0.000 1.35 1.35 550 70.70.04 19.0 10.0 0.2 0.14.73 0 0 0 Example 28 Example 550 9 9 0.1 0.000 0.0405 0.300 0.300 0.000 0.04 0.000 0.000 0.000 550 0.000 74.8 0.000 0.000 20.0 0.000 5.0 0.000 5.000 0 0.0000.2 0.000 0.000 0 0 0 (mass%)

Ag 29 Example 550 10 10 6.1 2.025 0.000 2.03 550 73.9 20.0 6.0 0 0.1 0 0 0 Co = 0.1 0.0405 0.405 2.025 4.725 4.725 1.08 1.35 1.35 1.35 1.35 4.05 30 Example 550 5 7 8.1 2.71.08 0.000 2.70 550 64.4 25.0 2.710.0 0.3 0.3 5.4 0 0 0 Cu 31 Example 550 7 9 12.2 4.05 0.000 4.05 550 62.2 30.0 7.012.2 00.6 15.0 14.2 0.214.2 0 16.2 0 0 1.2 3.2 3.2 4.1 4.1 4.1 4.1 0.1 6.1 8.1 Zn 32 Example 550 9 Average cooling rate 9 15.0 0 5.000 5.00 550 62.2 30.0 7.0 0.6 0.2 0 0 0 350°C 33 Example 550 2 4 450- 14.2 4.725 0.000 4.73 550 60 30.0 9.0 0.3 0.7 0 0 0 (°C/sec) 12 10 14 13 34 Example 550 2 14 14.2 4.725 9 5 5 8 8 0.000 4.73 550 8 60 9 30.0 9.0 7 9 9 4 0.3 0.7 0 0 0 450°C 35 Example 550 5 13 550- 16.2 5.4 0.000 5.40 550 57.4 30.0 12.0 0.5 0.1 0 0 0 10 10 12 12 10 Pre-annealing

temperature 9 5 5 9 5 7 9 2 2 5 (°C) 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550

[0107] Comparative Comparative

Example Example Example Example Example Example Example Example Example Example Example Example Example Example Example

[Table 1B] Type

[0106] [0107]

No. 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35

Y = 0.01 Sb = 0.1 Pb = 0.1 Nb = 0.1 Others In 0.1 Sr 0.1 Li = 0.1 Ti = 0.1 Zr = 0.1 W = 0.1 P = 0.1

[Table 1C] Cu + Ag

(mass%) component bath Plating (mass%) component bath Plating 0 0 0 0 0 0 0 0 Manufacturing 0 0 method 0 0 0 0 0 0 0 0 0 0 0 Ag Pre-annealing Average cooling rate Diffusion-plated layer No. Type temperature 0 0 0 0 0 0 0Bath 0 0 0 0 0 Plating 0 0bath component 0 0 0 0 0 0 0(mass%) (°C/sec) (mass%) (°C) Cu temperature 550- 450- 0 0 0 0.5 Zn Cu Ag 1.2 Σ 0 0 0 0(°C) 0 Zn 0 0Al 0 Mg 0 Ca0 0Si 0 Cu0 0Ag 0 Cu0+ Ag0 0Others 0.4 1.5 1.5 1.8 2.0 1.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 450°C Si 350°C 0.1

36 Example 600 4 6 18.2 6.075 0 0 0.000 0.2 6.08 0.4 0.2 550 0.2 59.5 0.5 35.0 0.5 5.0 0.2 0 0.2 0.2 0.5 0.2 0 0.2 0.2 0 0.2 0.2 0 0.2 0.2 Ca 0.1 Comparative 37 550 15 25 0 0.8 0 0.27 0 0.000 0.2710.0 600 60 0 15.0 35.0 5.0 0 0 0 0 0 Example 10.0 10.0 Manufacturing method 5.0 5.0 5.0 7.0 9.0 5.0 5.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 Mg Comparative 38 550 15 5 35.0 35.0 0.8 35.0 0.2735.0 0.000 35.0 0.2740.0 42.0 600 42.0 44.0 60 44.0 35.0 45.0 5.0 12.0 012.0 12.0 0 12.0 012.0 12.0 0 12.0 12.00 12.0 12.0 Example Al 39 Example 550 10 8 59.5 0.2 0.0675 0.00057.8 54.6 0.0749.2 46.3 600 46.3 57.8 49.2 35.0 38.5 7.0 80.3 0.1 80.3 0.1 80.3 80.3 080.3 0 80.3 80.3 0 80.3 80.3 80.3 Zn 48 40 Example 550 7 1 20.3 60 6.7560 0.000 6.75 600 54.6 35.0 9.0 0.2 1.2 0 0 0 temperature

41 Example 550 Bath 10 8 24.3 8.1 0.000 8.10 600 49.2 40.0 10.0 0.4 0.4 0 0 0 Y = 0.01 (°C) 550 600 600 600 600 600 600 600 600 600 600 550 550 550 550 550 550 550 550 550 550 42 Example 550 10 8 20.3 6.75 0.000 6.75 600 46.3 42.0 10.0 0.2 1.5 0 0 0 42

Comparative 43 550 6 2 6.08 28.4 0.27 0.07 9.450.27 0.000 9.458.10 6.75 6.75 600 9.45 46.3 4.05 1.35 42.0 0.41 10.0 1.36 0.2 1.36 1.5 1.36 1.36 01.36 1.36 0 1.36 1.36 0 1.36 1.36 layer Diffusion-plated layer Diffusion-plated Example 44 Example 550 9 1 0.000 12.2 0.000 4.05 0.000 0.000 0.000 4.05 0.000 0.000 0.000 600 0.000 49.2 0.000 0.000 44.0 0.000 5.0 0.680 0 0.680 1.8 0.680 0.680 0 0.680 0.680 0 0.680 0 0.680 0.680 0.680 (mass%)

45 Example 550 6 Ag 6 4.1 1.35 0.000 1.35 600 38.5 44.0 15.0 0.5 2.0 0 0 0 0.0675 Comparative 6.075 0.405 0.675 0.675 0.675 0.675 0.675 0.675 0.675 0.675 0.675 0.675 0.27 6.75 6.75 9.45 4.05 1.35 46 550 9 Cu 9 1.2 0.4050.27 0.000 0.418.1 600 48 45.0 5.0 0.5 1.5 0 0 0 Example 20.3 20.3 28.4 12.2 47 Example 470 9 9 18.2 0.8 2.0 0.6750.8 0.2 0.680 1.3624.3 550 80.3 4.1 12.0 1.2 7.0 2.0 2.0 0.2 2.0 0.5 2.0 02.0 2.00 2.0 2.0 0 2.0 2.0 In = 0.1 Zn Average cooling rate

48 Example 470 9 350°C 9 2.0 0.675 0.680 1.36 550 80.3 12.0 7.0 0.2 0.5 0 0 0 Sr = 0.1 450- 49 Example 470 9 (°C/sec) 9 25 2.0 0.675 0.680 1.36 550 80.3 12.0 7.0 0.2 0.5 0 0 0 Li = 0.1 50 Example 470 9 450°C 9 6 2.0 0.675 5 8 1 8 8 0.680 1.36 550 2 1 6 80.3 12.0 9 7.0 9 9 9 9 9 9 9 9 9 9 0.2 0.5 0 0 0 Sb = 0.1 550- 51 Example 470 9 9 15 2.0 0.67515 0.680 10 1.3610 10550 80.3 12.0 7.0 0.2 0.5 0 0 0 Pb = 0.1 Pre-annealing 52 Example 470 temperature 9 9 4 2.0 0.675 0.680 7 1.36 550 6 9 6 80.3 12.0 9 7.0 9 9 9 9 9 9 9 9 9 9 0.2 0.5 0 0 0 P = 0.1 53 Example 470 9(°C) 9 600 2.0 550 0.675550 0.680 550 550 1.36550 550 550 550 80.3 550 12.0 550 550 7.0 470 0.2 470 0.5 470 470 0470 470 0 470 0 470 470 Ti = 0.1 470

54 Example 470 9 9 2.0 0.675 0.680 1.36 550 80.3 12.0 7.0 0.2 0.5 0 0 0 Nb = 0.1 55 Example 470 9 9 Comparative 2.0 Comparative 0.675 0.680 1.36 550 Comparative 80.3 12.0 Comparative 7.0 0.2 0.5 0 0 0 Zr = 0.1 Example Example Example Example Example Example Example Example Example Example Example Example Example Example Example Example Example Example Example Example Example

56 Example

[Table 1C] 470 Type 9 9 2.0 0.675 0.680 1.36 550 80.3 12.0 7.0 0.2 0.5 0 0 0 W = 0.1

No. 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56

Corrosion

current density + SST 43 Performance

Corrosion

potential E C D D D E E D B S C S D B D C D E E D

[0108] + SST

[Table 2A] E B B C D E E D B A C C C B C C D E E D (*) 12 23 23 16 31 33 Expression 0 4 4 0 0 0 4 0 8 5 0 0 0 4 ß phase region 0.86 0.86 0.86 0.87 0.88 0.88 0.88 0.88 0.88 0.95 0.95 0.95 0.95 0.95 0.85 (4) - Plated layer - - - - Performance Adhesion Corrosion No. Chemical composition (mass%) fraction GDS analysis β phase region Corrosion amount Area current 15 14 11 12 13 14 (*) potential CAZmax/ Area density (g/m2) Zn Al Mg Ca Si Cu Ag 0 Cu + Ag 7Others 0 2 8 0CAZmin CAZmax 2 6 7Expression 6 8 0 0 2 + SST CAZmax/ CAZmin CAZmin fraction (4) + SST 10.00 1.04 1.09 1.04 1.09 1.04 1.04 1.04 1.04 1.09 1.01 1.01 1.09 1.04 1.00 1.04 1.04 1.46 1.30 1.00 1 135 85.2 10.0 4.0 0.2 0.2 0.2 0.2 0.4 0.0004 0.0040 10.00 0 - 0 E E 2 135 83.2 11.0 5.0 0.2 GDS analysis 0.2 0.2 0.2 0.4 0.0023 0.0024 1.04 15 0.86 12 B C CAZmax 0.0040 0.0024 0.0025 0.0024 0.0024 0.0024 0.0024 0.0024 0.0052 0.0120 0.0142 0.0142 0.0012 0.0051 0.0013 0.0028 0.0026 0.0035 0.0030 0.0023 3 145 83.2 11.0 5.0 0.2 0.2 0.0 0.4 0.4 0.0023 0.0025 1.09 14 0.86 4 B D 4 135 82.79 12.0 5.0 0 0.01 0.2 0 0.2 Ce = 0.1 0.0023 0.0024 1.04 7 0.86 4 C D 135 82.79 12.0 5.0 0 0.01 0.2 CAZmin 0 0.2 La = 0.1 0.0022 0.0024 1.09 8 0.87 0 D D 0.0004 0.0023 0.0023 0.0023 0.0022 0.0023 0.0023 0.0023 0.0050 0.0110 0.0140 0.0140 0.0011 0.0049 0.0013 0.0027 0.0025 0.0024 0.0023 0.0023

6 135 82.8 12.0 5.0 0 0 0.2 0 0.2 0.0023 0.0024 1.04 0 - 0 E E 7 135 82.8 12.0 5.0 Plated layer 0 0 0.2 0 0.2 0.0023 0.0024 1.04 0 - Cr = 0.5% 0 E E Ce = 0.1 La = 0.1 La = 0.1 La = 0.1 Ce = 0.1 Bi = 0.1 Sn = 0.1 Others V = 0.1 Y = 0.1 43

8 135 82.79 12.0 5.0 0 0.01 0.2 0 0.2 La = 0.1 0.0023 0.0024 1.04 2 0.88 4 D D La = 0.1 9 135 81.3 12.0 6.0 0 0.3 Cu + Ag 0.3 0.1 0.4 0.0050 0.0052 1.04 11 0.88 23 B B Ce = 0.1 0.4 0.4 0.4 0.2 0.2 0.2 0.2 0.2 0.4 1.0 1.0 1.0 0.2 0.4 0.1 0.3 0.2 0.3 0.2 0.2 10 135 79.3 12.0 7.0 0.2 (mass%) composition Chemical (mass%) composition Chemical 0.5 0.5 0.5 1.0 Bi = 0.1 0.0110 0.0120 1.09 12 0.88 31 A S 11 135 79.3 12.0 7.0 0.2 0.5 0.5 0.5 0.2 0.2 1.00.4 0.0140 0.0142 0.1 0.5 0.5 1.01 0.5 0.1 13 0.88 0.1 0.0 0 0.1 C C Ag 12 135 79.3 12.0 7.0 0.2 0.5 0.5 0.5 1.0 0 0 0 0 0 0.0140 0.0142 1.01 2 0 0 0.88 33 0 0 C S Cu 0.2 0.2 0.0 0.2 0.2 0.2 0.2 0.2 0.3 0.5 0.5 0.5 0.1 0.4 0.1 0.2 0.2 0.2 0.2 0.2 13 135 79.79 15.0 5.0 0 0.01 0.1 0.1 0.2 Sn = 0.1 0.0011 0.0012 1.09 6 0.95 8 C D 0.01 0.01 0.01 0.01 0.01 14 135 77.4 15.0 7.0 0.1 0.1 0.4 0.2 0 0.2 0.40.2 0.0049 0.3 0.0051 0.5 0.5 1.04 0.5 140.1 0.1 0.2 0.95 0.2 23 B B Si 15 135 75.8 19.0 5.0 0 0.1 0.1 0 0.1 V = 0.1 0 0 0.0013 0.0013 1.00 7 0 0 0.95 5 C D Ca 0.2 0.2 0.2 0.2 0.2 0.2 0.1 16 135 74.5 19.0 6.0 0 0.2 0.2 0.1 0.3 Y = 0.1 0.0027 0.0028 1.04 6 0.95 16 C C 4.0 5.0 0 0 0 0 0 5.0 5.0 5.0 5.0 5.0 6.0 0 7.0 7.0 0 0 0 0 0 0 0 5.0 6.0 6.0 5.0 5.0 5.0 17 135 74.6 19.0 6.0 0 0.2 0.2 Mg 0.0 5.0 0.2 Cr = 0.5% 0.0025 0.0026 1.04 7.0 5.0 8 7.0 0.95 0 D D 18 135 82.7 12.0 5.0 0 0 0.2 10.0 0.1 11.0 11.0 0.3 12.0 12.0 12.0 12.0 0.0024 12.0 0.003512.0 12.0 12.0 1.46 12.0 15.0 0 15.0 19.0 19.0 - 19.0 12.0 0 12.0 12.0 E E Al 19 135 82.8 12.0 5.0 0 0 0.2 0 0.2 82.79 82.79 0.0023 82.79 0.0030 1.30 79.79 0 - 0 E 82.79 E 85.2 83.2 83.2 82.8 82.8 81.3 79.3 79.3 79.3 77.4 75.8 74.5 74.6 82.7 82.8 20 135 82.79 12.0 5.0 0 0.01 Zn 0.2 0 0.2 0.0023 0.0023 1.00 2 0.85 4 D D Adhesion amount (g/m²)

[Table 2A] 135 135 145 135 135 135 135 135 135 135 135 135 135 135 135 135 135 135 135 135

[0108]

No. 10 11 12 13 14 15 16 17 18 19 20 1 2 3 4 5 6 7 8 9

Corrosion

current density 44 + SST Performance

Corrosion C S S S C E E D S S S S S S S potential

[0109] + SST

C A C A A E E C A A A A A C A

[Table 2B] (*) 18 34 33 35 35 33 31 33 33 32 35 Expression 0 0 0 2 ß phase region 0.95 0.98 0.88 0.85 1.10 1.10 1.00 0.95 0.95 0.95 0.90 0.90 0.90 (4) Plated layer - - Performance Adhesion Corrosion No. Chemical composition (mass%) fraction GDS analysis β phase region Corrosion amount Area current 12 13 13 13 12 12 1311 13 (*) potential CAZmax/ Area Expression density (g/m2) Zn Al Mg Ca Si Cu Ag 8 Cu + Ag 3 Others 0CAZmin 0 8 CAZmax + SST CAZmax/ CAZmin CAZmin + SST 4fraction (4) 1.02 1.06 1.14 1.27 1.00 1.05 1.03 1.02 1.04 1.02 1.02 1.02 1.01 1.21 21 135 72.1 19.0 8.0 0.3 0.3 0.3 0 0.3 Mo =1.030.1 0.0041 0.0042 1.02 8 0.98 18 C C 22 135 69.5 19.0 10.0 0.4 0.1 GDS analysis 0.8 0.2 1.0 B = 0.1 0.0123 0.0130 1.06 12 0.88 34 A S CAZmax 0.0042 0.0130 0.0140 0.0142 0.0146 0.0170 0.0170 0.0005 0.0220 0.0330 0.0520 0.0520 0.0630 0.0630 0.0762 23 135 69.5 19.0 10.0 0.4 0.1 0.8 0.2 1.0 B = 0.1 0.0123 0.0140 1.14 3 0.85 33 C S 24 135 69.7 19.0 10.0 0.2 0.1 1.0 0 1.0 0.0140 0.0142 1.01 13 1.10 35 A S 25 135 69.7 19.0 10.0 0.2 0.1 1.0CAZmin 0 1.0 Mo = 0.1 0.0141 0.0146 1.03 13 1.10 0 A C 0.0041 0.0123 0.0123 0.0140 0.0141 0.0134 0.0140 0.0005 0.0210 0.0320 0.0510 0.0500 0.0620 0.0620 0.0750

26 135 69.7 19.0 10.0 0.2 0.1 1.0 0 1.0 0.0134 0.0170 1.27 0 - 0 E E 27 135 69.7 19.0 10.0 0.2 0.1 1.0 0 1.0 0.0140 0.0170 1.21 0 - 0 E E Plated layer 44

Mo = 0.1 Mo = 0.1 Co = 0.1 Others B 0.1 B 0.1 28 135 74.77 20.0 5.0 0 0.2 0.0 0 0.0 0.0005 0.0005 1.00 8 1.00 2 C D 29 135 72.4 20.0 6.0 0 0.1 1.5 0 1.5 Co = 0.1 0.0210 0.0220 1.05 13 0.95 35 A S Cu + Ag 30 135 62.4 25.0 10.0 0.3 0.3 2.0 0 2.0 0.0320 0.0330 1.03 12 0.95 33 A S 0.3 1.0 1.0 1.0 1.0 1.0 1.0 0.0 1.5 2.0 3.0 3.0 3.5 3.5 4.0 31 135 59.2 30.0 7.0 0.6 (mass%) composition Chemical (mass%) composition Chemical 0.2 3.0 0 3.0 0.0510 0.0520 1.02 12 0.95 31 A S 32 135 59.2 30.0 7.0 0.6 0.2 0.0 3.0 0.2 3.00.2 0.0500 0.0520 1.04 3.0 13 0.95 33 A S Ag 33 135 56.5 30.0 9.0 0.3 0.7 3.5 00 3.5 0 0 0 0 0 0 0 0 0.0620 0.0630 1.02 11 0.90 33 A S Cu 0.3 0.8 1.0 1.0 1.0 1.0 0.0 1.5 2.0 3.0 0.0 0 0 0 3.5 34 135 56.5 30.0 9.0 0.3 0.7 3.5 0 3.50.8 0.0620 0.0630 1.02 3.5 44.0 0.90 32 C S 35 135 53.4 30.0 12.0 0.5 0.1 4.0 0 0.3 0.1 4.00.1 0.1 0.1 0.1 0.0750 0.1 0.2 0.3 0.10.0762 0.2 1.02 0.7 0.2 0.7 130.1 0.90 35 A S Si

Ca 0.3 0.4 0.4 0.2 0.2 0.2 0.2 0.3 0.6 0.6 0.3 0.3 0.5

10.0 8.0 10.0 10.0 10.0 10.0 10.0 0 0 5.0 6.0 10.0 7.0 7.0 9.0 9.0 12.0 Mg 19.0 19.0 19.0 19.0 19.0 19.0 19.0 20.0 20.0 25.0 30.0 30.0 30.0 30.0 30.0 Al 74.77 72.1 69.5 69.5 69.7 69.7 69.7 69.7 72.4 62.4 59.2 59.2 56.5 56.5 53.4 Zn Adhesion amount

[Table 2B] (g/m²) 135 135 135 135 135 135 135 135 135 135 135 135 135 135 135

[0109]

No. 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35

Corrosion

current 45 density + SST Performance

Corrosion D E E D A A A E S S E S S S S S S S S S S potential + SST

[0110] B E E C B B B E A A E A A A A A A A A A A

[Table 2C] (*) 36 34 40 31 31 31 31 31 31 31 31 31 31 31 31 Expression 0 0 0 2 0 0 ß phase region 1.10 1.10 1.10 1.10 1.00 1.10 1.20 1.10 0.95 0.95 0.95 0.95 0.95 0.95 0.95 0.95 0.95 0.95 - - Plated layer1.10 Performance (4)

Adhesion Corrosion No. Chemical composition (mass%) fraction GDS analysis β phase region Corrosion amount Area current 11 11 11 11 11 12 12 12 12 12 12 12 12 12 12 (*) 12potential Area Expression density (g/m2) Zn Al Mg Ca Si Cu Ag 0Cu +0Ag 6Others CAZmin 3 CAZmax 0 CAZmax/ + SST CAZmax/ + SST CAZmin CAZmin fraction (4) 1.02 1.00 1.00 1.03 1.00 1.30 1.02 1.00 1.13 1.09 1.09 1.09 1.09 1.09 1.09 1.09 1.09 1.21 36 135 55 35.0 5.0 0 0.5 4.5 0 4.51.35 0.0810 0.0823 1.02 1.09 111.09 1.10 0 B D 37 135 59.8 35.0 5.0 0 0 GDS analysis 0.2 0 0.2 0.0024 0.0029 1.21 0 - 0 E E CAZmax 0.0823 0.0029 0.0031 0.0080 0.0990 0.1000 0.1000 0.3900 0.0660 0.0270 0.0090 0.0120 0.0120 0.0120 0.0120 0.0120 0.0120 0.0120 0.0120 0.0120 0.0120 38 135 59.8 35.0 5.0 0 0 0.2 0 0.2 0.0023 0.0031 1.35 0 - 0 E E 39 135 57.75 35.0 7.0 0.1 0.1 0.1 0 0.1 0.0080 0.0080 1.00 6 1.00 2 C D 40 135 49.6 35.0 9.0 0.2 1.2 5.0 CAZmin 0 5.0 0.0990 0.0990 1.00 11 1.10 36 B A 0.0810 0.0024 0.0023 0.0080 0.0990 0.0970 0.1000 0.3000 0.0650 0.0270 0.0080 0.0110 0.0110 0.0110 0.0110 0.0110 0.0110 0.0110 0.0110 0.0110 0.0110

41 135 43.2 40.0 10.0 0.4 0.4 6.0 0 6.0 Y = 0.01 0.0970 0.1000 1.03 11 1.10 34 B A 42 135 41.3 42.0 10.0 0.2 1.5 5.0 0 5.0 0.1000 0.1000 1.00 11 1.10 40 B A Plated layer 45

Y = 0.01 Sb = 0.1 Pb = 0.1 Nb = 0.1 Zr = 0.1 In = 0.1 Sr 0.1 Li 0.1 Ti = 0.1 W = 0.1 Others 43 135 39.3 42.0 10.0 0.2 1.5 7.0 0 7.0 0.3000 0.3900 1.30 3 1.20 P 0.1 0 E E 44 135 46.2 44.0 5.0 0 1.8 3.0 0 3.0 0.0650 0.0660 1.02 11 1.10 31 A S Cu + Ag 45 135 37.5 44.0 15.0 0.5 2 1.0 0 1.0 0.0270 0.0270 1.00 12 1.10 31 A S 4.5 0.2 0.2 0.1 5.0 6.0 5.0 7.0 3.0 1.0 0.3 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 46 135 47.7 45.0 5.0 0.5 (mass%) composition Chemical (mass%) composition Chemical 1.5 0.3 0 0.3 0.0080 0.0090 1.13 0 1.10 0 E E 47 135 79.3 12.0 7.0 0.2 0.5 0.5 1 1.0 In = 0.1 0.0110 0.0120 1.09 0.5 0.5 120.5 0.5 0.95 0.5 0.5 31 0.5 0.5 A 0.5 S 48 135 79.3 12.0 7.0 0.2 0.5 Ag 0.5 0.5 1.0 Sr = 0.1 0.0110 0.0120 1.09 12 0.95 31 A S 0 0 0 0 0 0 0 0 0 0 0 1 4.5 0.2 0.1 5.0 7.0 3.0 1.0 0.3 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 49 135 79.3 12.0 7.0 0.2 0.5 Cu 0.5 0.5 1.00.2 Li =5.0 0.1 6.0 0.0110 0.0120 1.09 0.5 120.5 0.95 31 A S 50 135 79.3 12.0 7.0 0.2 0.5 0.5 0.5 0.5 1.0 Sb =1.2 0.1 0.1 0.4 0.0110 1.5 1.5 1.80.0120 1.5 1.09 0.5 0.5 0.5 120.5 0.5 0.95 0.5 0.5 31 0.5 0.5 A 0.5 S Si 51 135 79.3 12.0 7.0 0.2 0.5 0.5 0.5 0 0 1.0 Pb = 0.1 0.0110 0.01202 1.09 12 0.95 31 A S 0.1 0.2 0.4 0.2 0.2 0.5 0.5 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 52 135 79.3 12.0 7.0 0.2 0.5 Ca 0.5 0.5 1.0 P = 0.1 0.0110 0.0120 1.09 12 0.95 31 A S 53 135 79.3 12.0 7.0 0.2 0.5 0.5 0 0 0 5.0 0.5 5.0 1.0 5.0 7.0 Ti =9.0 0.1 10.0 10.0 0.0110 10.0 0 5.0 15.0 0.0120 5.0 7.0 1.09 7.0 7.0 127.0 7.0 7.0 0.95 7.0 7.0 31 7.0 7.0 A S Mg 54 135 79.3 12.0 7.0 0.2 0.5 0.5 0.5 35.0 35.0 1.035.0 Nb =35.00.1 35.0 40.0 0.0110 42.0 42.0 0.0120 44.0 44.0 45.0 12.0 1.09 12.0 12.0 1212.0 12.0 12.0 0.95 12.0 31 12.0 12.0 A 12.0 S 55 135 79.3 12.0 7.0 0.2 0.5 Al 0.5 0.5 1.0 Zr = 0.1 0.0110 0.0120 1.09 12 0.95 31 A S 57.75 43.2 59.8 59.8 49.6 41.3 39.3 46.2 37.5 47.7 79.3 79.3 79.3 79.3 79.3 79.3 79.3 79.3 56 135 79.3 12.0 7.0 0.2 0.5 0.5 Zn 0.5 55 1.0 W = 0.1 0.0110 0.0120 1.09 79.3 1279.3 0.95 31 A S Adhesion amount (g/m²)

[Table 2C] 135 135 135 135 135 135 135 135 135 135 135 135 135 135 135 135 135 135 135 135 135

[0110]

No. 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56

INDUSTRIAL APPLICABILITY

[0111]

According to the above-described aspects of the present invention, it is possible

to provide the hot-dip plated steel material capable of minimizing white rust generated at

5 the initial stage of corrosion.

the initial stage of corrosion.

[0111]

INDUSTRIAL APPLICABILITY

0% or more and 0.25% or less of Pb,

47 0% or more and 0.25% or less of Sb,

0% or more and 0.3% or less of Mo, CLAIMS 0% or more and 0.5% or less of Cr,

[Claim 1] A hot-dip plated steel material comprising: 0% or more and 1.0% or less of Ni,

a steel material; and 0% or more and 0.3% or less of Li,

a plated layer disposed on a surface of the steel material, wherein 0% or more and 0.3% or less of Sr,

0% or more and 0.3% or less of Ce, 5 the plated layer has a chemical composition including, in terms of mass%, 0% or more and 0.3% or less of La,

more than 10.0% and less than 45.0% of Al, 0% or more and 0.3% or less of Y,

4.0% or more and 15.0% or less of Mg, 0% or more and 0.6% or less of Ca,

0% or more and 0.3% or less of In, 0.01% or more and 2.0% or less of Si, and 0% or more and 0.3% or less of Bi,

at least one of 0.03% or more and 5.0% or less of Cu, or 0.03% or more and 0% or more and 0.7% or less of Sn,

10 6.0% orincluding further less of Ag, and 6.0% or less of Ag, and further including at least one of 0.03% or more and 5.0% or less of Cu, or 0.03% or more and

0% or more and 0.7% or less of Sn, 0.01% or more and 2.0% or less of Si, and

0% or more and 0.3% or less of Bi, 4.0% or more and 15.0% or less of Mg,

more than 10.0% and less than 45.0% of Al, 0% or more and 0.3% or less of In, the plated layer has a chemical composition including, in terms of mass%,

15 0% or more and 0.6% or less of Ca, a plated layer disposed on a surface of the steel material, wherein

0% or more and 0.3% or less of Y, a steel material; and

[Claim 1] A hot-dip plated steel material comprising: 0% or more and 0.3% or less of La, CLAIMS 0% or more and 0.3% 47 or less of Ce,

0% or more and 0.3% or less of Sr,

20 0% or more and 0.3% or less of Li,

0% or more and 1.0% or less of Ni,

0% or more and 0.5% or less of Cr,

0% or more and 0.3% or less of Mo,

0% or more and 0.25% or less of Sb,

25 0% or more and 0.25% or less of Pb,

Claims

an area fraction of a ß phase is 3% or more in a cross section along a thickness

48
[Claim 2] The hot-dip plated steel material according to claim 1, wherein

CAZ 0% or(3). 0.1000 more and 0.5% or less of B, 0.0005 CAZ (2) 0% or more and 0.5% or less of P, CAZmax/CAZmin 1.20 (1)

0% or more and 0.25% or less of Ti, Expressions (1) to (3),

0% or more and 0.25% or less of Co, maximum value CAZ of CAZ and an absolute minimum value CAZ of CAZ satisfy

5 0% or more and 0.25% or less of V, 2/3t position from the surface of the plated layer is denoted by CAZ, an absolute

concentration to a concentration of Zn in an internal region between a 1/3t position and a

0% or more and 0.25% or less of Nb, denoted by t, and a ratio of a total concentration of a Cu concentration and an Ag

0% or more and 0.25% or less of Mn, surface of the plated layer toward the steel material, a thickness of the plated layer is

analysis using a glow discharge optical emission spectrometry in a direction from a 0% or more and 0.25% or less of Zr, in a case where, in an elemental distribution profile obtained by quantitative

0% or more and 0.25% or less of W, a total amount of Cu and Ag satisfying 0.03% or more and 6.0% or less, and

10 0% or more and 5.0% or less of Fe, and a remainder of Zn and impurities, and

0% or more and 5.0% or less of Fe, and a remainder of Zn and impurities, and 0% or more and 0.25% or less of W,

a total amount of Cu and Ag satisfying 0.03% or more and 6.0% or less, and 0% or more and 0.25% or less of Zr,

in a case where, in an elemental distribution profile obtained by quantitative 0% or more and 0.25% or less of Mn,

0% or more and 0.25% or less of Nb, analysis using a glow discharge optical emission spectrometry in a direction from a 0% or more and 0.25% or less of V,

15 surface of the plated layer toward the steel material, a thickness of the plated layer is 0% or more and 0.25% or less of Co,

denoted byandt, 0.25% 0% or more and or a ratio less ofof Ti,a total concentration of a Cu concentration and an Ag

0% or more and 0.5% or less of P, concentration to a concentration of Zn in an internal region between a 1/3t position and a 0% or more and 0.5% or less of B,

2/3t position from the surface 48 of the plated layer is denoted by CAZ, an absolute

maximum value CAZmax of CAZ and an absolute minimum value CAZmin of CAZ satisfy

20 Expressions (1) to (3),

CAZmax/CAZmin ≤ 1.20 ... (1)

0.0005 ≤ CAZmin ... (2)

CAZmax ≤ 0.1000 ... (3).

[Claim 2] The hot-dip plated steel material according to claim 1, wherein

25 an area fraction of a β phase is 3% or more in a cross section along a thickness direction of the plated layer, and concentrations of Al, Zn, Cu, and Al in the β phase satisfy Expression (4),

0.85 ≤ [Al]/([Zn] + [Cu] + [Ag]) ≤ 1.15 ... (4)

wherein, each of [Al], [Zn], [Cu], and [Ag] in Expression (4) is a quantitative

5 analysis value (at%) obtained by energy dispersive X-ray spectrometry in the β phase.
[Claim 3] The hot-dip plated steel material according to claim 1 or 2, wherein 10 or

more (Zn + Al) - (Cu + Ag) compounds having an average grain size of 1 μm or more are

contained as intermetallic compound particles within a range of 10000 μm2 in a cross

section along the thickness direction of the plated layer.

10

section along the thickness direction of the plated layer.

contained as intermetallic compound particles within a range of 10000 µm² in a cross

more (Zn + Al) - (Cu + Ag) compounds having an average grain size of 1 µm or more are

[Claim 3] The hot-dip plated steel material according to claim 1 or 2, wherein 10 or

analysis value (at%) obtained by energy dispersive X-ray spectrometry in the ß phase.

wherein, each of [Al], [Zn], [Cu], and [Ag] in Expression (4) is a quantitative

0.85 [Al]/([Zn] + [Cu] + [Ag]) 1.15 (4)

concentrations of Al, Zn, Cu, and Al in the ß phase satisfy Expression (4),

direction of the plated layer, and