JPH01100231A - Copper alloy for high tensile electric and electronic equipment - Google Patents

Abstract

PURPOSE:To obtain the titled copper alloy having excellent corrosion resistance, solderability and heat resistant at low cost by specifying the compsn. consisting of Ni, Al, Zn, etc., Cr, etc., and Cu, regulating its O2 and S contents and furthermore specifying its crystal grain size. CONSTITUTION:The titled copper alloy is contg., by weight, 3.5-10.0% Ni and 0.2-4.0% Al, contg. 0.005-5.0% total of one or more kinds among 0.05-5.0% Zn, 0.01-5.0% Mn, 0.001-0.8% Mg, 0.001-0.8% Ca, 0.05-1.0% Cd and 0.001-0.5% Ag, furthermore contg. 0.005-1.0% total of one or more kinds among 0.005-4.0% Cr, 0.001-0.4% V, 0.005-0.4% Ti, 0.001-0.2% Y, 0.005-0.2% Zr, 0.005-0.4$ Co, 0.005-0.4% Fe-P compounds (FexPy), 0.005-4.0% Cr-P compounds (CrxPy) and 0.005-0.4% Co-P compounds (CoxPy) and the balance consisting of Cu with inevitable impurities; in which <=100ppm O2, <=10ppm S and 20mum crystal grain size are furthermore regulated. Said alloy has various excellent characteristics.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention has excellent strength, corrosion resistance, solderability, heat resistance, and bending workability, and is suitable for manufacturing precision parts for miniaturized electrical and electronic equipment. This invention relates to copper alloys for electrical and electronic equipment.

[Conventional technology] Lead materials for electrical and electronic equipment, especially connectors, switches, sockets, contact springs, and semiconductors (ICs, transistors, etc.) have various characteristics such as strength, bending workability, fatigue properties, stress relaxation properties, and stress corrosion cracking resistance. Materials with excellent properties such as durability and heat resistance are required. 42 alloy (F e -42w
Fe-Ni alloys such as 52wt%Ni), 52wt%Ni (Fe-52wt%Ni), Qu-3e alloys, and Cu-Ti alloys are known, but these alloys are expensive. Furthermore, due to its characteristics, Fe--Ni alloys have problems such as insufficient strength. Further, Cu-Ni-3n spinodal alloys are known, but they are difficult to manufacture and have poor product reliability. Due to these circumstances, Cu-8n alloy,
That is, phosphor bronze, especially phosphor bronze for springs containing 6 to 8 wt% Sn (hereinafter wt% is abbreviated as %) is often used.

[Problem that the invention seeks to solve]

The above-mentioned phosphor bronze for springs has a strength of only about 60 to aoKy,'= which is insufficient for miniaturizing precision parts for electrical and electronic equipment, and also causes deterioration of solder joint strength over time and susceptibility to corrosion cracking. This is a major flaw in practical terms. For this reason, the above-mentioned Cu-Be alloys and the like are used in some parts, but the cost is an obstacle to lowering costs.

In recent years, electrical and electronic equipment has been trending toward smaller size and higher integration, and in order to respond to the strength of the Cu alloy used in these devices and the trend toward surface mounting during mounting, it is necessary to improve solder joint strength, Sn, 5n-
Pb alloy plating is required to have improved adhesion reliability and to be inexpensive for use in large quantities.

In order to meet these demands and replace conventional alloys, alloys with higher performance and lower cost performance are required.

That is, (1) It must have a certain degree of conductivity while maintaining high strength of 80 Ky/- or more.

(2) Low cost.

(3) High reliability in bending workability during molding into electrical and electronic equipment parts. In other words, the bending surface should have dimensional accuracy without any cracks or the like.

(4) Workability, corrosion resistance, stress corrosion cracking resistance, fatigue properties,
Excellent stress relaxation properties.

(5) Solder joint strength: The adhesion of 3N and 3N-PB alloy plating is stable over a long period of time.

(6) In addition to 3n and 3n alloys, Au and A
Plating such as y, Nr, etc. is often used, and the plating properties of these are also excellent.

(Means for Solving the Problems) In view of this, as a result of various studies, the present invention has particularly excellent strength, bending workability, fatigue properties, stress relaxation properties, stress corrosion cracking resistance, heat resistance, etc., and is miniaturized. Precision parts for electrical and electronic equipment,
For example, we have developed a copper alloy for high-strength electrical and electronic equipment that is suitable for connectors, switches, sockets, contact springs, leads for semiconductors (ICs and transistors), etc.

That is, one of the alloys of the present invention has l'4i of 3.5 to 10.0%.
and Al0.2-4.0%, and Z n0.05-5.
0%.

Mn 0.01-5.0%, Mg0.001-0.
8%, Ca0.001~0.8%, Cd0105~1
．． 0%, any one within the range of Ag0.001 to 0.5%
Contains a total of 0.005 to 5.0% of one or more species, further Cr01OO5 to 0.4%, V0.001 to 0.4%
, T i 0.005~0.4%, Y0.001~
0.2%, Zr0.005-0.2%.

Co0.4%, Fe-P compound (FexPy) 0.
005-0.4%, Or-P compound (Cr x Py
) 0.005-0.4%, Go-P compound (cox
Py) Contains any one or two or more types within the range of 0.005 to 0.4% in a total of 0.005 to 1.0%, the balance being C
It consists of u and inevitable impurities, and further has an O2 content of 110
0pp or less, S content 10ppm or less, grain size 2
It is characterized by having a thickness of 0 μm or less.

Another alloy of the present invention is Ni3.5-10, o%
and A 10.2-4.0%, Zn 0.05-5.
0%, Mn0.01~5.0%, Mg0.001~
0.8%, Ca0.001-0.8%, cd0.0
5-1.0%.

Contains one or more of A y in the range of 0.001 to 0.5% in a total of 0.005 to 5.0%, and further contains Cr
0.005~0.4%, V0.001~0.4%,
Ti0.005-0.4%, YOlool ~0.2
%, Zr0.005-0.2%, Co0.4%, Fe
-P compound (F ex Py ) 0.005 to 0.4
%, Cr-P compound (Cr x Py ) 0.005
~0.4%.

Co-P compound (Cox Py) 0.005-0.
Any one or two or more types within the range of 4% total 0,00
Contains 5 to 1.0%, and 0.03% or less of Pb.

In 0.03% or less, Ga 0.05% or less, Ge0.
05% or less, As 0.01% or less, Sb 0.05% or less, Bi 0.02% or less, Te 0.05% or less, [3e0
．． Less than 5%.

30.05% or less, rare earth elements 0.05% or less, Si0
．． A total of 0 of any one or two or more types within a range of 5% or less
．． Contains 5% or less, the balance consists of Cu and unavoidable impurities,
Furthermore, the O2 content is 1100pp or less, and the S content is tOp.
pm or less, and the crystal grain size is 20 μm or less.

The alloy of the present invention is mixed into an ingot that is melted and cast with the above composition.
Manufactured by hot and cold working and heat treatment. For example 7
Hot working is carried out by heating and holding at 00 to 1000°C, and after finishing, cooling is performed by water cooling, etc., and the surface is cleaned by milling, sieving, or pickling, and then cold processing such as cold rolling and handling is carried out. After that, it is manufactured by combining aging heat treatment and cold working or solution treatment, aging heat treatment, and cold working. In addition, after the final cold working, it is
In combination with temper annealing for 24 hours to 24 hours, a tension leveler, tension annealing, etc., it is possible to correct the shape and remove residual distortion, thereby obtaining higher properties. It is also possible to manufacture the alloy of the present invention by casting it by a continuous casting method, directly performing cold working or heat treatment to homogenize the structure, and then subjecting it to heat treatments such as cold working, aging, and compacting.

[For production]

The alloy of the present invention is produced by the above manufacturing method, and has a strength of 80 to 150 Klf/mix and an elongation of 2 to 150 Klf/mix, depending on the alloy composition.
20. It exhibits a characteristic of electrical conductivity of 10 to 40% lAC3, effectively dispersing the N1xAiy compound or the N1xAj2yCuz compound, and making it possible to improve strength and springiness, as well as conductivity and heat resistance. However, Ni was added to 3,5
~10.0% and Al at 0.2~4.0% because if either the Ni content or the He1 content is less than the lower limit, sufficient strength and springiness cannot be obtained. This is because if it exceeds this, soldering properties will deteriorate and workability, especially hot workability, will deteriorate, impairing manufacturability.

Soldering of the group consisting of Zn, Mn, l'tl, Ca, Cd, and Ag (hereinafter referred to as element group A) not only suppresses deterioration of reliability later on, but also exhibits deoxidizing and desulfurizing effects, and improves the castability of the alloy. Suppresses the occurrence of defects during hot working. It also shows moves to prevent electrical short circuits caused by migration. However, Zn0.0
5-5.0%.

Mn0.01~5.0%, Mg0.001~0.8%
, Ca0.001-0.8%, Cd0.05-1.0%
, A90, 001 to 0.5%, the reason why any one or two or more species were limited to a total of 0.005 to 5.0% is that sufficient effects cannot be obtained below the lower limit. This is because if the upper limit is exceeded, the integrity of the ingot will be impaired and productivity will be significantly reduced.

Next, Cr, ■, T*, Y, zr, co.

Fex Py, Crx Py, Cox Py (
The group consisting of elements B (hereinafter referred to as element group B) has a large effect on suppressing the growth of crystal grains during heat treatment such as solution treatment, obtaining good ductility as a microstructure, and improving bending formability. It also shows the effect of improving hot workability and greatly contributes to the ease of 'lJ manufacturing. However, Cr0.005-0.4%,
V0.001-0.4%.

T i 0.005~0.4%, Y0.001~0
．． 2%, Zr0.005-0.2%, Co0.4
%, FexPy 0.005-0.4%, Cr x
Py 0.005-0.4%, Cox Py 0
．． Any 7') 11 or 2 within the range of 0.005 to 0.4%
The reason for limiting the amount of 0.005% to 1.0% in total is that if the lower limit is less than the lower limit, a sufficient effect will not be obtained, and if the upper limit is exceeded, the castability will be reduced, and the solder wettability, plating property, etc. This is because it worsens the processability and further deteriorates the workability.

Furthermore, Pb, In, Ga, Ge, As, and Sb.

The group consisting of B i , Te; Be, B, rare earth elements, si<a, C element P ¥) improves free machinability and significantly suppresses press die wear. However, Pb0.0
3% or less, In 0.03% or less, Ga 0.05% or less, Ge 0.05% or less, As 0.01% or less, Sb 0.
0.05% or less, Bi 0.02% or less, Tea.

0.05% or less, [3e 0.5% or less, 30.05% or less, rare earth elements (RE) 0.05% or less, Bi 0.5% or less, and a total of 0.5 of any one or two or more of them The reason why the content is limited to % or less is that if the content exceeds this range, the castability, hot workability, etc. will be greatly reduced, and the electrical conductivity and repeated bendability will also be reduced. The alloy of the present invention has the above composition and further has an O2 content of 100 ppm or less, thereby containing Nix, Aiy compounds or N1
It is effective in finely and uniformly dispersing the xAiyCuz compound, and contributes to improved soldering properties and plating properties.

However, if the O2 content exceeds this, not only will the above effects not be seen, but the O2 content will not only become coarse, but also cause the properties such as strength and plating properties to deteriorate.
It was limited to pm or less.

Also, by setting the S content to 10 ppm or less, N! xAiy compound or Nix, AlyCuz
It is effective in finely and uniformly dispersing compounds, improves hot workability, and also works to suppress abnormal growth of plating materials.

However, if the content exceeds this range, hot workability will be greatly reduced and manufacturability will be impaired. Furthermore, the S content is reduced to 10p because it forms sulfides with the constituent elements of the alloy of the present invention, reducing mechanical properties such as strength and springiness, and greatly inhibiting plating properties.
It was limited to pm or less. The grain size greatly affects bending formability, especially the smoothness of the surface of the bent part, and if it exceeds 20 μm, the surface of the bent part will noticeably lack smoothness, causing large wrinkles and cracks, which will shorten the life of the part.・Crystal grain size is 2
0 μ? Limited to W or less.

In addition, as for P that does not form a compound, its content is 0.0
It is desirable that it be 3% or less. Further, the dispersed particles in the alloy of the present invention are desirably 10 μTrt or less in order to suppress deterioration of plating properties, bending properties, and strength.

〔Example〕

The present invention will be described below with reference to Examples.

Example (1) A copper alloy having the composition shown in Table 1 was melted and cast to a thickness of 5OI.
An nIr11 ingot with a width of 120 # and a length of 200 m was obtained.

After face-cutting this and homogenizing it at 880℃ for 6 hours,
It was hot rolled at 30°C and cooled with water to form a plate with a thickness of 10 m. For these plates, cold rolling and intermediate annealing (63
0°C for 1 hour) was repeated, and a plate thickness of 0.4 m was subjected to solution treatment (held at 920°C for 2 minutes and water cooled), and the final processing rate was 40.
After finishing the plate with a thickness of 0.25 m and subjecting it to temper annealing at 420°C for 1 hour, various test pieces were cut out to determine the strength,
The conductivity, bending formability (R/l), plating adhesion, solder joint strength, and stress corrosion cracking resistance were investigated. These results are shown in the second
Shown in the table.

Strength is based on JIS Z2241, conductivity is based on JIS
Measured based on l 0505. Bending formability (R/l)
is tested based on the block method of JIS Z2248, and the minimum bending radius that causes cracks on the surface of the test piece (
R) divided by the thickness (1) of the test piece. Plating adhesion is 30X30. After cleaning the surface of the test piece, Ag
After plating, heat it in the air and observe the blisters on the plating surface. Those with no blisters after heating at 550'C for 5 minutes are marked as rOJ, and those with 1 to 3 blisters are marked as "rOJ". ∆” marks, and those larger than that are shown as “x” marks. Regarding the solder joint strength, connect oxygen-free copper lead wires to a 20 x 25 m test piece so that the solder area is 9# in diameter.
A tensile test was performed on the 40 pieces that were joined by solder and subjected to an accelerated heating test at 150°C for 500 hours, and those whose strength was 70% or more of the strength before the accelerated heating test were marked rOJ, 5
Mark "△" for 0 to 70%, mark "x" for less than that.
Represented by a mark.

Stress corrosion cracking resistance is NH3 based on JIS C8306.
A constant load test was conducted in a 3vo1% atmosphere with a tensile load of 30KFJf/rrvn, and the time until cracking occurred was measured.

Example 2 An alloy having the composition shown in Table 3 was cast using a 01 dome continuous casting machine, and the thickness was 10. A coil ingot with a width of 85 m was obtained. This was annealed at 750°C for 10 hours, then subjected to repeated cold rolling and intermediate annealing (1 hour at 610°C).
Solution treatment with plate thickness of # (held at 920℃ for 2 minutes and then water cooled)
was finished to a plate with a thickness of 0.25 m at a final processing rate of 40%, and temper annealed at 400°C for 1 hour.
Each characteristic was measured in the same manner as in 1). In addition, regarding press mold abrasion resistance, after performing 1 million punches using a coil newly slit to a width of 45 #11 from the above material, the surface of the mold was observed with a scanning electron microscope for 12 days. The degree of wear was investigated. The results are shown in Table 4.

As is clear from Tables 1, 2, 3, and 4, the alloys Nα1-10 and 18-23 of the present invention are superior in strength, conductivity, and solder joint strength to the conventional alloy Nα17. It can be seen that it has excellent stress corrosion cracking resistance.

On the other hand, comparative alloy Nα12 with high Nr and Al contents
In this case, significant cracks occurred during hot working, making it impossible to manufacture the test material. Comparative alloy Nα13, which contains too many A and B element groups, similarly failed to produce a sound ingot and also cracked during hot working. Therefore, sample material h (17) could not be obtained. Also, A,
Comparative alloy No. 0.0 that does not contain B and C element groups. In No. 11, the crystals became coarse, impairing bending formability, and significantly deteriorating plating adhesion and solder joint strength.

Furthermore, the comparative alloy Nα11, which has a large content of ■, has greatly inferior bending formability and plating adhesion, and also has deteriorated solder joint strength. Comparative alloy Nα15, which has a high S content, caused severe cracking during hot working, while comparative alloy N0.12. N0
．． Similarly to No. 13, no sample material was obtained. Furthermore, even if the composition is the same as that of the alloy Nα13 of the present invention, the 98%
Comparative alloy No. 0'CX1 hour. In No. 16, the crystal grains became coarse and the bending formability was greatly impaired.

It can be seen that the alloys Nα18 to Nα23 of the present invention containing the C element group have excellent abrasion resistance of press dies. On the other hand, the comparative alloy Nα24, which does not contain the C element group and has large crystal grains, has extremely poor wear resistance of the press die, and the crystal grains are large or zero.
Comparative alloy No. 25 with too much zffi. In N026, even with the inclusion of C element, the wear resistance of the press mold showed only a slight improvement.

〔Effect of the invention〕

Thus, according to the present invention, strength, electrical conductivity (thermal conductivity)
, has excellent bending workability and stress corrosion abrasion resistance, greatly improves solder reliability (joint strength, heat peeling resistance) and plating reliability, and has good abrasion resistance of press dies, making it suitable for electrical and electronic equipment, such as It is useful as connectors, switches, sockets, contact springs, semiconductor (IC, transistor) leads, terminals, heat exchangers, etc., and has a remarkable industrial effect such as making electrical and electronic equipment smaller and more precise. It is something to do.

Claims (2)

[Claims] (1) Ni3.5-10.0wt% and Al0.2-4.
Contains 0wt%, Zn0.05-5.0wt%, Mn0
．． 01-5.0wt%, Mg0.001-0.8wt%
, Ca0.001-0.8wt%, Cd0.05-1.
0 wt%, Ag 0.001 to 0.5 wt%, a total of 0.005 to 5.0 wt% of any one or two or more types.
Contains Cr0.005-0.4wt%, V0.00
1-0.4wt%, Ti0.005-0.4wt%, Y
0.001~0.2wt%, Zr0.005~0.2w
t%, Co0.005-0.4wt%, Fe-P compound (Fe_xP_y) 0.005-0.4wt%, Cr-
P compound (Cr_xP_y) 0.005 to 0.4 wt%
, Co-P compound (Co_xP_y) 0.005-0.
A total of 0.4 wt% of any one or two or more types.
A copper alloy for high-strength electrical and electronic equipment, containing 0.005 to 1.0 wt%, the balance being Cu and unavoidable impurities, and further having an O_2 content of 100 ppm or less, a S content of 10 ppm or less, and a crystal grain size of 20 μm. (2) Ni3.5-10.0wt% and Al0.2-4.
Contains 0wt%, Zn0.05-5.0wt%, Mn0
．． 01-5.0wt%, Mg0.001-0.8wt%
, Ca0.001-0.8wt%, Cd0.05-1.
0 wt%, Ag 0.001 to 0.5 wt%, a total of 0.005 to 5.0 wt% of any one or two or more types.
Contains Cr0.005-0.4wt%, V0.00
1-0.4wt%, Ti0.005-0.4wt%, Y
0.001~0.2wt%, Zr0.005~0.2w
t%, Co0.005-0.4wt%, Fe-P compound (Fe_xP_y) 0.005-0.4wt%, Cr-
P compound (Cr_xP_y) 0.005 to 0.4 wt%
, Co-P compound (Co_xP_y) 0.005-0.
A total of 0.4 wt% of any one or two or more types.
Contains 005 to 1.0 wt%, and further includes Pb 0.03 wt% or less, In 0.03 wt% or less, Ga 0.05 wt% or less, Ge 0.05 wt% or less, As 0.01 wt% or less,
Sb 0.05wt% or less, Bi 0.02wt% or less, T
e0.05wt% or less, Be0.5wt% or less, B0.
05wt% or less, rare earth elements 0.05wt% or less, Si
Contains any one or two or more types within a range of 0.5 wt% or less, a total of 0.5 wt% or less, the remainder consisting of Cu and unavoidable impurities, furthermore, the O_2 content is 100 ppm or less, the S content is 10 ppm or less, A copper alloy for high-strength electrical and electronic equipment with a grain size of 20 μm.