JPS58217660A - Amorphous alloy - Google Patents

Abstract

PURPOSE:To enhance the strength, amorphous forming capacity, corrosion resistance and brittleness resistance during heating of an alloy, obtained by using a specific composition containing Mo, C and B and substantially comprising the remainder Fe. CONSTITUTION:This amorphous alloy has a composition which comprises 4- 30atomic% Mo, 15-30atomic% C+B and the remainder Fe and inevitable impurities and of which the C/(C+B) ratio is 0.05-0.95.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an amorphous alloy that has excellent mechanical strength and corrosion resistance, can be easily turned into an amorphous state, and has a high resistance to embrittlement when heated.

Normally, metals or alloys are in a crystalline state in the solid state, but under certain conditions they acquire an atomic structure that does not have a crystalline structure similar to that in the liquid state, and this is called an amorphous alloy. It has been pointed out that amorphous alloys may have significantly superior mechanical properties compared to practical alloy materials produced by conventional conventional melting methods.

Many examples of these high-strength amorphous alloys have been disclosed. Among them, JP-A-54-1 by Masumi et al.
Using C as the amorphous forming element of No. 05750,
I'm-based amorphous alloys containing C'r, No, or W are materials that are attracting attention because of their high mechanical properties, corrosion resistance, and economic efficiency. Also, JP-A-52-5620, 54-97515, 54-9 by Ray et al.
7526 and JP-A-55-84 by Freerich et al.
Ft-based amorphous alloys that use B as an amorphous-forming element and include (:r, Mo, F, etc.), as disclosed in No. 805, are said to have particularly high mechanical properties.

However, these alloys have some drawbacks in various properties. Alloys containing B as an amorphous forming element are more expensive than alloys containing C.

Although it has high strength and amorphous formation ability, it has poor corrosion resistance and is expensive, so it has some disadvantages in terms of economy. On the other hand, alloys containing C are corrosion resistant.

Although it is excellent in economical efficiency, it is inferior to alloys containing B in terms of strength and amorphous formation ability. Additionally, both of these alloy systems suffer from the problem of embrittlement when heated below the crystallization temperature, for example at 400υ.

The ribbon-shaped sample can maintain the toughness to allow complete contact bending at 180° for about 300 minutes at most, and it cannot be said that it is a material that can sufficiently withstand use from 9.5 ooυ to near the crystallization temperature.

The present invention has high strength, excellent amorphous formation ability, and excellent corrosion resistance from one or more viewpoints.

The present invention provides an alloy with high resistance to embrittlement when heated.

Specifically, the present invention is an amorphous alloy having a primary composition. That is, %No 4-5o atom%.

C'10B 15-60 atomic%, balance free of iron and impurities, cut'/(C+B) ratio 105-0.95
In a preferred embodiment, Cl(t'0B)
The ratio is 0.20~”o,a.

It is an alloy that is

As is already known, alloys that easily change to an amorphous state are basically transition metals such as F and B.

It is known that an amorphous alloy with semimetallic elements such as P@Si is added, but the present invention is a special combination thereof.1 The inventor has discovered that an amorphous alloy having the above composition range It has been newly discovered that it has excellent mechanical properties and corrosion resistance, is attractive when turned into an amorphous state, and has a high resistance to embrittlement when heated.

The amorphization of the alloy of the present invention is achieved at a cooling rate of about 10" seconds or higher obtained by the commonly used single-roll method, twin-roll method, centrifugal quenching method, or melt spinning method. Amorphization is achieved by a semimetallic Mainly achieved by B and C of N.

facilitates this. According to the study results of the present inventors, there is no transition metal element other than No that has an effect on the same level as MO.

It is known that there is a large difference in the amorphous formation ability between B and ClIC, as the Fa-82 element can be amorphized, but Fc-C cannot. By adding No.
Although it is possible to increase the amorphization formation ability, at a cooling rate of about 105 A/sec, Pg -M
It is extremely difficult to make an o-C alloy amorphous. The main feature of the present invention is to add C'' as a metalloid element and MO as an element that promotes B amorphization.

The reasons for limiting the ingredients of the present invention will be described below.

(C+B) has 15 to 50 atoms. Less than 15 atoms.

If the number exceeds 30 atoms, it becomes difficult to make it amorphous. Further, the C7 (c1B) ratio is 005 to 0.95.

If it is less than 0.05, the degree of embrittlement upon heating increases and corrosion resistance and moisture resistance deteriorate, and if it exceeds 0.95, embrittlement upon heating increases and it becomes difficult to turn into amorphous.

No has a concentration of 4 to 30 atoms, but if it is less than 4M atoms, it becomes difficult to make it 1° amorphous and the corrosion resistance decreases. If it exceeds 30 at %, it becomes difficult to make it amorphous. Further, as one aspect of the present invention, it is preferable that the C7(t'+B) ratio is 0.20 to 0.80, since embrittlement upon heating is further reduced.

Examples of the present invention will be described below.

Example 1 Table 1 shows the hardness, tensile fracture strength, alpha alpha-forming ability, corrosion resistance, moisture resistance, and embrittlement resistance of the alloy of the present invention in comparison with comparative examples.

The ability to form an amorphous layer is as follows: 1. When a ribbon-shaped sample is prepared using the normal single-roll method, the maximum thickness of the sample confirmed by Xfs and optical microscopic observation of the surface indicates that the sample is completely amorphous. . Corrosion resistance was expressed as the corrosion rate when a ribbon-like sample with a thickness of 0.02 vm and a width of 2 cm made by the twin roll method was immersed in a 30v aqueous solution of 1 NEcl. Moisture resistance was measured by exposing a sample using the twin roll method to an atmosphere with a humidity of 95% and a temperature of 30 V, and showing the time required for rust to develop. The embrittlement resistance during heating is as follows: * Ribbon-shaped sample was heated for 5 minutes under reduced pressure of o-4 Torr.

When a bending test is performed, the temperature at which it breaks during bending,
It is expressed as a parameter known as the so-called embrittlement temperature.

As can be seen from the table, the alloy of the present invention has high hardness.

In addition to having tensile fracture strength and amorphous formation ability, it has a low corrosion rate in fNH(,'l) and a humidity of 9
It takes a long time for rust to develop in the air, and has high corrosion resistance and moisture resistance. In particular, the C"/(C'+B) ratio is 005 to 0.
．． Because K is in the range of 95, the embrittlement temperature is higher than that of the comparative example alloys.

Some of the alloys of comparative examples are comparable in properties to the alloys of the present invention, but none have all of the properties, and overall the embrittlement temperature is lower. For example, Alloys 11 and 15 have poor hardness, tensile strength, and amorphous formation ability, and also have low embrittlement temperatures. Alloy 15.
No. 17 has poor amorphous formation ability and slightly low embrittlement temperature. Alloy 12.14 has poor corrosion resistance and moisture resistance, and has a slightly low embrittlement temperature. Alloys 16 and 18 have a difference in embrittlement temperature from the alloys of the present invention, but are inferior in corrosion resistance. Alloy 19 has the ability to form an amorphous state.

Poor moisture resistance and low embrittlement temperature. Alloy 20 has poor amorphous formation ability, corrosion resistance, moisture resistance, and low embrittlement temperature.

Example 2 The gt diagram shows the embrittlement temperature and C')'CC'+B) of Fg6BMO6(B*'')26 amorphous alloy.
It is a graph showing the relationship between ratios.

As is clear from this, the sea embrittlement temperature changes depending on the ratio of CI (C+B) and increases rapidly between 0 and 0.05 and between 1 and 095. CI(C+B) is approximately 0.05
In the range of 0.95 to 0.95, the embrittlement temperature is much higher than that in the range of 0 to 1, respectively. Further 0.20 to 0.
80 was found to be stable and high (, No content, and even if the (C + B) amount was changed, the maximum value existed between this range. Therefore, if CI (C + B) was adjusted to be between this range, An alloy with substantially high thermal stability can be obtained.

As described above, the alloy of the present invention has excellent mechanical strength, corrosion resistance, high amorphous formation ability, and high resistance to embrittlement when heated, making it an overall superior alloy compared to conventional alloys. It is a practical material for cutlery materials and various structural members, and its industrial value is large.

[Brief explanation of the drawing]

Figure 1 is a graph showing the dependence of the embrittlement temperature on the Fg6eMo6(B,C)26 amorphous alloy and the (,V(C1B) ratio. Title of the invention: A, l, a, meeting. Person making the amendment Detailed Description of the Invention and Drawings. Contents of Amendment L The scope of the claimed claims is amended as follows: [LMO4-30 atomic% l(0+B) 15-30 atomic%, balance F8 and impurities, and 0/(0
+B) Amorphous alloy having a ratio of αo5 to α95. & 0/(0+B) ratio is α20 to α80, the amol 7 Tes alloy according to claim 1. ”2 The column for detailed explanation of the invention in the specification is corrected as follows. (1) Add "After 54-97526J" on page 2, line 7 of the specification. (2) Same book, page 3, line 12 1'-0+BJ as r(0+B
) Correct to J〇(8) “Fe
-B2 element J to r 1o5/# cooling rate Fe-8
Correct to 2 elements J. (4) Replace Table 1 on page 9 of the circular with the attached Table 1. ! Correct the drawing as follows: 0 Replace Figure 1 with the attached Figure 1. that's all

Claims (1)

[Claims] An amorphous alloy that is P-0,95. 2. The amorphous alloy according to claim 1, wherein the C/(C+B) ratio is from 0.20 to 0.80.