JPS6246278B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a composite metal material consisting of copper or copper alloy and aluminum or aluminum alloy;
Furthermore, the present invention relates to a method of manufacturing this copper-clad aluminum wire as a composite metal material.

Conventionally, composite materials of copper and aluminum or their alloys, as represented by copper-clad aluminum wire, are often used for electric wires, etc., and are inexpensive, have good conductivity, and can be electrically insulated by alumite treatment. Composite materials made of aluminum and copper, which have excellent electrical contact resistance, plating properties, and solderability, are widely used as electrical equipment parts.

Common methods for producing these composite materials include, for example, a method in which a copper pipe and an aluminum rod are fitted together and extruded at the same time, or a method in which a copper plate and an aluminum plate are simultaneously rolled.

However, when composites manufactured by these methods are exposed to high temperatures of approximately 350°C or higher, a harmful metal layer consisting of an intermetallic compound of copper and aluminum is formed at the composite interface, significantly reducing the bonding strength of the interface. It is well known that Therefore, in the past, processing methods were adopted that ensured that the two materials were never exposed to high temperatures of 350°C or higher after joining, and the conditions of use had to be similarly controlled.

Therefore, if the annealing temperature of both materials is below 350℃, such as a composite material of pure copper and pure aluminum, it can be put to practical use if it is manufactured with sufficient care and the conditions of use are limited. It has been impossible to create such a composite material in cases where the heating temperature required for annealing is approximately 450°C or higher, such as with silver, nickel silver, and phosphor bronze.

The present invention has been made to improve these drawbacks, and in order to prevent the formation of a copper-aluminum intermetallic compound at the boundary between the two materials, a nickel layer is interposed at the boundary. This discovery led to the method of the present invention.

In carrying out the present invention, a nickel layer is formed on part or all of the surfaces of one or both of copper or copper alloy material and aluminum or aluminum alloy material, which will be the bonding interface, and then the two materials are bonded. Bye.

When the above composite material is a copper-clad aluminum wire, two copper-nickel composite strips are rolled and welded around the aluminum wire, or one copper-nickel composite strip is rolled and welded around the aluminum or aluminum alloy wire. A method such as seam welding and pulling out is advantageously used.

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

Example 1 Using the device shown in Fig. 1, the thickness of 2 mm and the width of
100mm aluminum strip 1, thickness 0.2mm, width 100mm
After degreasing and annealing the nickel strip 2, the wire diameter is 0.2
Wire brush 4 made of mmφ stainless steel wire
The aluminum-nickel composite strip 3 having a cross section as shown in FIG. 2a was obtained by purifying it in steps a and 4b and rolling it in one pass to a thickness of 1 mm in a four-high rolling mill 5.

This was passed through a heat treatment device 10 consisting of a margon gas atmosphere furnace 8 heated to 550° C. and a cooling section 9, and then wound onto a winder 6'. Next, this was cold rolled to a thickness of 0.8mm and slit to a width of 5mm, resulting in an aluminum plate with a thickness of 0.8mm and a width of 5mm.
A nickel composite strip and nickel silver 6 with a thickness of 2 mm and a width of 100 mm were processed in the same manner as above using the equipment shown in Figure 1 to form a three-layered aluminum-nickel-nickel silver layer with a thickness of 1.2 mm and a width of 100 mm. Inlay strip 7 was obtained.

This was repeatedly subjected to normal cold rolling and annealing at 550°C to form a strip with a thickness of 0.2 mm, which was then slit to a width of 40 mm to form a three-layer inlay strip 7 with a cross-sectional shape as shown in Figure 2b. Finished.

This strip was punched out as an electrical component part,
Since no brittle Al-Cu compounds were formed at the interface, no defects such as peeling occurred.

Example 2 A copper rectangular wire 6 with a thickness of 5 mm and a width of 30 mm has a thickness of 10 mm on the surface.
After performing μ nickel plating 2, an aluminum plate with a thickness of 1 mm and a width of 30 mm is
7wt% silicon alloy 1 is rolled in one pass, and the thickness is 3.
mm, width 31mm cross-sectional shape is shown in Figure 2 c.
A layer clad board 7 was obtained. The heat treatment temperature at this time was 500°C.

This material was soldered to pure aluminum using an aluminum-7% silicon alloy as a brazing material and used as a connecting part for aluminum electric wires, but no peeling at the boundary was observed.

Example 3 A grooved roll 11 as shown in Fig. 3a was used to form a cross-sectional shape as shown in Fig. 2a with a thickness of 2 mm and a width of 12 mm.
Two copper-nickel composite strips (nickel layer thickness in each case is 0.2 mm) and three aluminum wires with a wire diameter of 5 mm were cleaned at the bonding interface with a wire brush, and then rolled at the same time and cross-sectioned. A three-layer composite wire of 1 copper, 2 nickel and 3 aluminum having an approximately circular shape with an outer diameter of about 5 mm as shown in FIG. 3b was obtained.

In order to adjust the shape, this composite wire was made to have an outer diameter of 4.9 mmφ using two peeling dies, then annealed at 400° C. for 1 hour, and further diced to an outer diameter of 2.6 mmφ. The resulting copper-clad aluminum wire has stronger bonding interface strength than conventional wires, especially
No embrittlement of the interface was observed even after long-term use at high temperatures of 250°C or higher. The reason why nickel was chosen as the metal to be interposed at the boundary is that nickel is difficult to form a brittle metal layer with copper or aluminum, and its processability is relatively similar to that of copper and aluminum. Joint part 1 as shown in b
2. Even if the nickel layer is partially exposed, its corrosion resistance is excellent, and even in the case of a diffusion layer made of a copper-nickel alloy, its corrosion resistance is as good as that of copper, as is known from so-called cypronickel or monel metal. It was chosen from a practical standpoint.

Example 4 As shown in Fig. 4, a copper material 6 with a thickness of 1 mm and a
Composite of nickel material 2 of 0.1mm, cross-sectional shape is 2nd
After cleaning the surface of a copper-nickel composite strip with a width of 25.6 mm as shown in Figure a,
It was wrapped around a 5.8 mmφ Al-0.2 wt% Zr alloy wire 1 and the joint 13 was seam welded with a torch 14 to obtain a composite wire 7 consisting of three layers of copper 6-nickel 2-aluminum alloy 1. .

This wire was drawn to an outer diameter of 2 mmφ by repeating wire drawing with a die and annealing at 450°C. This composite line could be used almost in the same way as in Example 3, but
During seam welding, the melting point of nickel is higher at 1455°C compared to copper's melting point of 1083°C, so copper can be welded with almost no melting of the nickel layer, so there is almost no nickel layer on the surface. This is advantageous in that it will not form.

In FIG. 4, a simple method using an inert gas arc is shown as a seam welding method, but if a high frequency seam welding method or the like is used, it is possible to achieve a more preferable joining although the equipment cost increases.

As explained above, according to the method of the present invention, since the formation of a copper-aluminum alloy layer due to thermal diffusion at the bonding interface is avoided, the usable temperature range is greatly improved, and copper alloys with annealing temperatures of 300°C or higher can be used. Alternatively, since it becomes possible to use aluminum alloy, there is an advantage that a high strength or heat-resistant composite wire can be manufactured.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a joining device used in Examples 1 and 2 of the present invention, and FIGS. 2 a, b, and c are aluminum-nickel composites obtained by Examples 1 and 2 of the present invention, Each cross-sectional view of an aluminum-nickel-copper composite material and an aluminum-nickel-copper composite material, FIG.
b is a cross-sectional view of a copper-nickel-aluminum composite wire obtained by this apparatus, and FIG. 4 is a cross-sectional explanatory view of a copper-nickel-aluminum composite wire obtained in Example 4 of the present invention. 1... Aluminum or aluminum material,
2... Nickel layer, 3... Aluminum-nickel composite material, 6... Copper or copper alloy material, 7... Copper-nickel-aluminum composite material.

Claims (1)

[Claims] 1. A copper-aluminum composite material characterized in that a nickel layer is interposed in part or all of the bonding interface between copper or a copper alloy material and aluminum or an aluminum alloy material to bond the two materials. Production method. 2. A nickel layer is formed on part or all of the surfaces of one or both of copper or copper alloy material and aluminum or aluminum alloy material, which will be the bonding interface, and then the two materials are bonded, as described in claim 1. A method for producing a copper-aluminum composite material. 3 Two copper-nickel composite strips with a nickel layer formed at the bonding interface of the copper or copper alloy material to the aluminum or aluminum alloy material are rolled and welded around the aluminum or aluminum alloy wire as the aluminum or aluminum alloy material. A method for manufacturing a copper-aluminum composite material according to claim 1 or 2, wherein both materials are bonded to form a copper-clad aluminum wire. 4. Seam welding one copper-nickel composite strip with a nickel layer formed at the bonding interface of the copper or copper alloy material to the aluminum or aluminum alloy material around the aluminum or aluminum alloy wire as the aluminum or aluminum alloy material and pulling it out. The copper-clad aluminum wire according to any one of claims 1 to 3, wherein both materials are bonded to form a copper-clad aluminum wire.
Method for manufacturing aluminum composites.