JPS62192548A - Dispersion strengthening heat resistant copper alloy material - Google Patents

Abstract

PURPOSE:To provide superior alloy strength, high electric conductivity and high thermal diffusivity by dispersing hard particles of an intermetallic compound having a specified particle size and ceramic particles having a specified particle size in a Cu matrix. CONSTITUTION:Hard particles of an intermetallic compound such as Cu-Fe having <=1mum particle size and particles of ceramics such as TaC, TiCN, B4C, Al2O3 or TiB2 having <=1,000Angstrom average particle size are dispersed in a Cu matrix to obtain a dispersion strengthening heat resistant Cu alloy material. This dispersion stengthening alloy material is produced by applying mechanical alloying technique. The alloy material has superior characteristics of both of conventional precipitation hardening and dispersion hardening alloys and can be utilized as a material for an electrode, electronic parts, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a dispersion-strengthened heat-resistant copper alloy material used for electrode materials, electronic component materials, and the like.

[Prior art and problems to be solved by the invention] In general, copper alloys used as electrode materials, high thermal conductivity materials, and high strength materials are classified into precipitation hardening type and dispersion hardening type. It is used and divided based on the following.

Precipitation hardening copper alloys include Cu-Or, Cu
-Cr-2r, Cu-1"e, Cu-Cd
Alloys such as are used. In these precipitation hardening copper alloys, intermetallic compound precipitated particles are uniformly dispersed and precipitated in the copper matrix by aging heat treatment, thereby imparting high alloy strength and good electrical conductivity.

However, since additive elements are added to increase the alloy strength, high thermal conductivity and electrical conductivity cannot be expected. In addition, it has excellent tensile elasticity up to 400°C, but at higher temperatures the alloy softens due to the dissolution of precipitated particles.
It has the disadvantage that the strength is significantly reduced.

On the other hand, dispersion-strengthened alloys are made by uniformly dispersing fine Viramix particles in a copper matrix, and have excellent IC strength up to near the melting point of the alloy, as well as excellent electrical conductivity and thermal conductivity. There is. However, while it has good heat resistance and strength in the relatively high temperature range of 300 to 600°C, it has the problem that mechanical properties such as strength, elongation, reduction of area, and fatigue strength are greatly affected by the manufacturing method. ing.

As general methods for manufacturing this dispersion-strengthened alloy, internal oxidation methods, mechanical alloying methods, chemical coprecipitation methods, etc. are known.

Although it is possible to uniformly disperse dispersed particles using the internal oxidation method, the alloy systems that can be produced are limited, and there are significant restrictions on the types of alloying elements to be added. The mechanical alloying method has almost no restrictions on alloy components or additions, and is a manufacturing method that is relatively suitable for mass production, but it has the drawback of requiring fine dispersed particles as raw materials. Furthermore, although the chemical coprecipitation method facilitates uniform dispersion, it poses problems such as contamination with impurities, waste liquid treatment, and restrictions on alloy components.

Each of the above! Dispersion-strengthened copper alloys manufactured using the II manufacturing method have excellent heat resistance, but the properties such as tensile strength, elongation, workability J3, and fatigue strength do not improve in the temperature range from room temperature to around 300°C. 6 tends to be slightly inferior to precipitation hardening type alloys.

Therefore, no conventional copper alloy material exhibits uniformly high strength over a wide temperature range from room temperature to high temperature.

Therefore, an object of the present invention is to provide a dispersion-strengthened heat-resistant copper alloy material that has excellent alloy strength from room temperature to high temperature, and also has high electrical conductivity and thermal diffusivity.

[Means and effects for solving the problem] As a result of various studies to solve the above problem, the inventors of the present invention have found that the present inventors have achieved high strength, excellent workability, and elongation in the temperature range from room temperature to around 300°C. By applying mechanical alloying technology, we have combined the characteristics of precipitation hardening alloys, which exhibit a It has been found that a copper alloy with high strength, high thermal conductivity, and high electrical conductivity can be obtained by

The present invention is a dispersion-strengthened heat-resistant copper alloy material characterized by containing intermetallic compound hard particles with a particle size of 1 μl or less and ceramic particles with an average particle size of 1000 Å or less in a copper matrix. Preferably, the dispersion-strengthened heat-resistant copper alloy material is characterized in that the ceramic particles are made of one or more of carbides, nitrides, oxides, and borides.

The present invention will be explained in detail below.

In order to increase the strength of a copper alloy without impairing its thermal conductivity and electrical conductivity, and to maintain excellent alloy strength even at high temperatures, it is necessary to select alloying elements, their addition amount, and solid solution amount. It is important to reduce the However, when the addition a and the amount of solid solution are reduced, the alloy strength is reduced. Therefore, as a result of investigating additives that increase strength without increasing thermal conductivity and electrical conductivity by 1t1, we found that ceramic particles, preferably ceramic particles of one or more of carbides, nitrides, oxides, and borides. It has been found that by adding it, strength can be increased without impairing electrical conductivity and thermal conductivity.

On the other hand, the strength can be increased by finely and uniformly dispersing these additives, but if too many are added, workability and elongation will be reduced. Further, in the temperature range from V temperature to about 300° C., hardening by precipitated particles of intermetallic compounds is better. Therefore, it is effective to create a copper alloy that combines the advantages of both the precipitation hardening type copper alloy and the dispersion strengthening type copper alloy. In other words, in the temperature range from room temperature to 300°C, the strengthening mechanism by precipitates is mainly used, and in the high temperature range above 300°C, the dispersion strengthening mechanism of ceramic particles is avoided, and the combination of both improves thermal conductivity and electrical conductivity. We found that it is effective to improve the

In addition, in order to make both of the strengthening mechanisms effective, it is necessary to make the particle size of the intermetallic compound 1 μl or less and the average particle size of the ceramic particles 1000Δ or less.

Here, the reason why the average particle size of the ceramic particles should be 1000A or less is because the finer the particle size, the more effective it is for strengthening, and if it becomes larger than 1000A, it becomes a starting point for fatigue fracture, rupture, etc., and workability deteriorates. This is to do so. The reason why the average particle size of the gold inter-ff compound particles is set to 1 μm or less is because when the particle size is larger than 1 m, workability in rolling, wire drawing, etc. becomes poor. However, if the particle size becomes too small, there will be a problem of reduced strength, so the optimum particle size is preferably 2000A to 5000A.

We have further discovered that a manufacturing method applying mechanical alloying technology is suitable as a method for manufacturing a dispersion-strengthened alloy having both precipitation hardening and dispersion strengthening mechanisms as described above. The internal oxidation method and the chemical coprecipitation method are not suitable for producing alloys with complex components because the alloy systems that can be used together are limited. In contrast, the mechanical 70ing method has fewer restrictions on alloys and can be applied to various alloys.

In the case of the present invention, it can also be manufactured by mixing and solidifying ceramic powder with an average particle size of 1000 A or less and Cu alloy powder, and then uniformly dispersing precipitate particles with a particle size of 1 μm or less by aging treatment. First, a binary copper-oxide alloy is made by an internal oxidation method or a chemical coprecipitation method, and then copper alloy powder is added to it and mechanical alloying is performed.

Note that in order to make the dispersion of ceramic particles by the mechanical 70ing method more uniform, it is desirable that the treatment time be longer than the time required to reach saturated hardness. Furthermore, in order to avoid contamination by impurities from the container or ball, it is desirable to wash the container or ball and lower the temperature inside the container.

[Example] Examples of the present invention will be described in detail below.

ELL2 Ceramic powders shown in Table 1 and copper alloy powders produced by Ar gas atomization were mechanically alloyed using a dry attritor device. Ar+Q.

In a 5%02 atmosphere, agitator rotation speed 135rl)m
Treated for 72 hours. The obtained composite powder was sieved and
Seed mesh and after 1 type 2 reduction (450℃ x 1 hour),
It was vacuum sealed and extruded into a copper pipe. The extrusion conditions were: extrusion temperature 880°C, holding time 2 hours, extrusion ratio 12:
The test was carried out under the conditions of 1.

Next, process about 20% with a roller die and
One 0mφ wire rod. Further aging treatment was performed, and the mechanical and physical properties of the resulting copper alloy were measured.

The results obtained are shown in Table 2. For comparison, Cu
-Cr-Zr precipitation hardening copper alloy (Cu-0゜5Cr-
0,22Zr) are included in Table 2 as a comparative example.
Show.

The alloys with experiment numbers @1 to 4 in Table 2 all contain ceramic particles of 1000A or less, and the average particle size of the intermetallic compound precipitated particles is 0.8 μJ.
It was 11 or less.

As is clear from Table 2, the dispersion-strengthened heat-resistant copper alloy material of the present invention was found to exhibit excellent strength, thermal conductivity, and electrical conductivity.

Δdan with an average particle size of 740△, ○2, B with an average particle size of 530A
, C and Ar gas atomization method copper alloy powder Cu
-7r-Cr was mechanically alloyed for 120 hours using a dry ball mill. The composition of the obtained powder was Cu-0,6Or-0,2Zr-0,5ΔQ20-
0.23-C11%), and the average particle size is approximately 260
It was μm. Next, in order to reduce excess oxide, 50
31 was heat-treated in H2 gas at 0° C. for about 1 hour, and then vacuum hot pressed to form a plate with a thickness of about 201111111. Vacuum degree 10-3 to -4, pressure 0.5t/c+a2, temperature 9
Hot pressing was carried out at 00°C. Next, it was hot rolled at 860° C. to achieve about 50% processing. A test sample was cut from this plate, and its structure was observed and its mechanical properties and physical properties were measured. The results are shown in Table 3.

As is clear from the third example, the copper alloy material of the present invention was found to have excellent thermal conductivity and electrical conductivity, and high strength. It also had excellent heat resistance.

In the above examples, a method using a mechanical alloying process was exemplified as a method for producing the copper alloy material of the present invention, but the present invention is not limited to products produced by this method, and may be produced by other methods. It should be made clear here that it may be manufactured.

[Effects of the Invention] As explained above, the present invention has the characteristics of both conventional precipitation-hardened alloys and dispersion-strengthened alloys,
It exhibits high strength, high thermal conductivity, and high electrical conductivity. Therefore, the copper alloy material of the present invention can be widely and effectively used as electrode materials, materials, electronic component materials, and the like.

Claims (2)

[Claims] (1) A dispersion-strengthened heat-resistant copper alloy material characterized by containing intermetallic compound hard particles with a particle size of 1 μm or less and ceramic particles with an average particle size of 1000 Å or less in a copper matrix. (2) The dispersion-strengthened heat-resistant copper alloy material according to claim 1, wherein the ceramic particles are made of one or more of carbides, nitrides, oxides, and borides.