JPS6023911B2 - Manufacturing method of clad obi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing metal clad materials, particularly aluminum striped clad strips.

Aluminum or aluminum alloys (hereinafter referred to as "aluminum") are deposited on various metal base materials.

) is clad in a striped shape, for example, an IC
It is used as a material for electronic components such as lead frames. Conventionally, aluminum stripe cladding bands have been generally manufactured as follows.

In other words, the parts of the base material strips to be clad (and if possible, the mating surfaces of the aluminum strips) are polished and cleaned with a wire brush in advance, overlapped, and crimped by rolling between the strips. Further, a diffusion annealing process is performed in which the material is heated to a temperature of 300 to 600° C. for a short period of time to complete the bonding. Thereafter, it is finished to a predetermined thickness by cross-rolling. However, when using the cladding material on a glass (including ceramics) sealing alloy base material, which is an important application of the aluminum striped clad strip, 50%
When heated to a temperature of around 0°C or higher, minute blisters occur in the clad aluminum.
Partial peeling may occur.

This now lowers the acceptance rate of the final product, so there is a need to provide cladding bands free of these defects. The cause of the above blistering, as seen by the inventors, is that the lubricating oil used to prevent scorching during cold rolling crimping scatters or permeates between the base plate and the aluminum strip. , it partially obstructs rolling and crimping, remains in that area, and decomposes and vaporizes and expands during subsequent heating.

However, until now, there have been no effective measures to prevent blisters. The present invention has been made with the intention of overcoming such problems, and is a method of manufacturing an aluminum stripe clad band by cladding aluminum strips in a stripe shape on a base material by cold rolling and bonding. , the cold rolling crimping is divided into two stages, and the first stage does not use rolling lubricating oil.
During the second stage of rolling crimping, rolling crimping is performed at a low reduction rate as long as the lubricating oil for rolling does not seep into the bonding surface between the aluminum and the base material, while avoiding scorching on the rolling rolls,
The second stage is characterized by rolling crimping using a rolling lubricant at a high reduction rate that provides sufficient bonding, thereby providing an aluminum cladding that does not blister when subsequently subjected to heating. The rolling reduction ratio in rolling crimping without using rolling lubricating oil in the first stage usually needs to be 8% or more in order to prevent the lubricating oil from seeping into the joint surfaces in the second stage.

On the other hand, if the rolling reduction rate is increased, phosphorus will stick to the roll, so
To avoid this, a reduction ratio of up to 25% must be selected, usually up to 15%. The optimal value varies somewhat depending on the combination of cladding materials, but
It can be found within 10%. The second stage rolling crimping is
Since lubricating oil is used, a high rolling reduction rate should be adopted to further strengthen the joint formed in the first stage.

Although the limit varies depending on the thickness of the cladding band to be manufactured, a reduction rate of at least 10%, preferably 30% or more is selected. In order to complete the bonding of the aluminum stripe cladding band and achieve the desired thickness, it may be necessary to perform diffusion annealing and random cold rolling in the method of the present invention.

Of course, the conditions may be in accordance with known techniques. It has been confirmed as follows that in the aluminum stripe clad strip produced according to the method of the present invention, the adhesion between the base material and aluminum is improved on average.

In other words, diffusion annealed clad material is corroded with caustic soda to remove aluminum, and Fe generated by diffusion is removed.
- When examining the state of clear coloring caused by AI compounds, the conventional ones have strong shading, that is, areas that are in close contact with each other,
It can be seen that while there are some areas where there is weak adhesion or no adhesion at all, according to the present invention, there is no dark or light appearance over the entire surface, and average adhesion is achieved. Example 1 42% of the base material is known as a glass sealing alloy.
A Ni-Fe strip with a thickness of 0.34 ribs and a width of 25 strips was used as the clad material, and pure aluminum (JISI07 target product) strips of 10 strips with a thickness of 4.6 strips and a width of 4.6 were used as the cladding material. did.

After polishing and cleaning the parts in contact with the base material aluminum with a wire brush, the aluminum strips were layered and passed through rolling rolls to a reduction rate of 11 without using rolling lubricating oil.
%, the first stage of rolling crimping is performed so that the plate thickness is on the 0.31 side, and then, using lubricating oil, the second stage of rolling crimping is performed at a rolling reduction rate of 13% to achieve a plate thickness of 0. It was set to the .27 side.
For comparison, a cladding band was also prepared in which the plate thickness was 0.27, which was the same as above, by using rolling lubricating oil as in the case of the sub-chassis, and performing single-stage rolling and crimping at a rolling reduction rate of 20%.

These cladding bands were held in a furnace with a non-oxidizing atmosphere of 550 qo with a sand gap of 3 mm, subjected to diffused brightness annealing, and then finished rolled to a plate thickness of 0.25 mm.

After the obtained product was held in a 530 qo furnace for 6 minutes, it was examined using a magnifying glass to see if minute blisters had occurred in the aluminum part.

While the product according to the present invention had no blisters, 11/10 blisters were observed in the comparative example.
Example 2 A Kovar alloy (29% Ni-16% Co-remaining Fe) strip with a thickness of 0.45 ribs and a width of 25 strips was used as the base material, and a strip of aluminum alloy (equivalent to JIS 2014) with a thickness of 1 mm was used as the cladding material. , the strips on the width 4.6 side were combined.

The first stage of rolling crimping is performed by rolling to a thickness of 0.41 skin at a rolling reduction rate of 9% without using rolling lubricating oil, and then the second stage of rolling crimping is performed using lubricating oil and rolling reduction rate of 0.41 skin. 34%, plate thickness 0.
It was rolled to the 27 side. In the comparative example, rolling crimping is carried out at a rolling reduction rate of 40% to a thickness of 0.27 using rolling lubricating oil. 55,000 for the same machine as Example 1
After performing diffusion bright annealing between ×3 inkstone sand, finish rolling was performed to make the product thickness 0.25 ribs.

Each cladding band was also subjected to a heating test of 530 qo x 6 minutes to examine the occurrence of fine blisters.

Claims (1)

[Claims] 1. In a method for manufacturing an aluminum stripe clad strip by cladding aluminum or aluminum alloy strips in stripes on a base material by cold rolling crimping, the cold rolling crimping is divided into two stages. , the first stage does not use rolling lubricating oil, and the rolling rolls are rolled at a low rolling reduction rate as long as the rolling lubricating oil does not seep into the joint surface between aluminum or aluminum alloy and the base metal during rolling crimping in the second stage. A manufacturing method characterized in that rolling crimping is performed while avoiding seizure of the material, and in the second stage, rolling crimping is performed using rolling lubricating oil at a high rolling reduction rate that provides sufficient bonding. 2. The manufacturing method according to claim 1, wherein the rolling reduction ratio in the first stage rolling crimping is 8 to 25%, and the rolling reduction ratio in the second stage rolling crimping is 10% or more. 3. The manufacturing method according to claim 2, wherein the rolling reduction ratio in the first stage rolling crimping is 8 to 15%, and the rolling reduction ratio in the second stage rolling crimping is 30% or more. 4. The manufacturing method according to claim 1, wherein diffusion annealing and finish rolling are sequentially performed following rolling and crimping. 5. The manufacturing method according to claim 1, wherein the base material is a glass sealing alloy.