JPH0571659B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to an improvement in a method for processing phosphor bronze, and in particular, to rationalize the manufacturing process by making hot processing possible. [Conventional technology] Generally Sn3~12wt%, P0.01~0.5wt%, balance
An alloy made of Cu is called phosphor bronze, and it is widely used as parts of electric ceramics and electronic devices because it has excellent strength and spring ferrous properties compared to other non-ferrous spring materials. However, since phosphor bronze has poor hot workability, it is processed exclusively by cold working, which inevitably increases the cost of the product. That is, when a phosphor bronze ingot is hot-rolled, large cracks occur on the surface of the rolled plate, making subsequent rolling impossible. Therefore, conventionally, processing has been carried out only by cold rolling. Furthermore, since phosphor bronze is highly work hardened, it is necessary to perform intermediate annealing many times, which complicates the manufacturing process and significantly increases costs. [Problems to be Solved by the Invention] The present invention has been made as a result of intensive research in view of the current situation.As a processing method for phosphor bronze, a phosphor bronze ingot is rolled by hot working, but compared to the case of cold working. We have developed a processing method that yields a product with a surface condition that is comparable to that of the previous one, that is, without any cracks. [Means for solving the problems] The method of the present invention uses Sn3 to 12wt%, P0.01 to 0.5wt%,
Processing rate of 10 to 30 for phosphor bronze ingots with remainder Cu
%, then cooled, heated again, and hot worked. That is, when a phosphor bronze ingot is subjected to hot working, for example, hot rolling, at various working rates, the first hot rolling rate is in the range of 10 to 30%, and then once cooled, it is heated again. It was discovered that no cracks were formed even when the copper alloy was subjected to about 90 to 95% hot rolling, which is the method used for ordinary copper alloys. In the method of the present invention, it is extremely important to perform the first hot working at a processing rate of 10 to 30%, and the reason for limiting this processing rate to 10 to 30% is that In some cases, insufficient processing results in insufficient formation of fine recrystallized grains during the cooling and reheating processes after hot processing, resulting in cracks on the surface when further hot processing is attempted. . Moreover, if it exceeds 30%, cracks will occur on the surface of the rolled plate, which will grow into large cracks during the second hot working. It is preferable that the heating temperature for hot pressing be in the range of 600 to 800℃; if it is less than 600℃, sufficient processing cannot be achieved, and if it exceeds 800℃,
This is because heating requires extra energy and is not economical. In some methods of the present invention, cooling is performed after hot working, but the temperature must be cooled to around room temperature. [Function] Since the method of the present invention can be carried out by hot working in a phosphor bronze processing method, processing can be carried out with extremely low deformation resistance compared to conventional cold working. In other words, since phosphor bronze is a hard copper alloy, cold working requires intermediate annealing as described above, which requires a huge amount of power and special tools, but hot working is not possible. Therefore, the power cost can be reduced and processing can be performed using ordinary tools without performing the above-mentioned intermediate annealing. [Example] After melting copper in a high-frequency melting furnace and adding Sn to it, deoxidizing it with P and casting by continuous water cooling casting, a phosphor bronze ingot (thickness: 100mm, width 250mm, 300Kg/1 charge)
was created. This ingot was heated in the range of 600° to 750°C, hot rolled at various processing rates, cooled to room temperature, and then heated again in the range of 600° to 750°C to a thickness of 10 mm. Then, hot rolling was performed to a thickness of 5 mm to obtain a phosphor bronze plate of the present invention. In order to compare with the phosphor bronze plate of the present invention, the above phosphor bronze ingot was rolled under conditions other than the method of the present invention as shown in Table 1 to obtain a comparative phosphor bronze plate. The thus obtained phosphor bronze plates of the present invention and comparative phosphor bronze plates were tested for the presence or absence of cracks on their surfaces. The results are shown in Table 1.

【table】

〔effect〕

As detailed above, the method of the present invention is extremely useful industrially, as it can shorten the manufacturing process and significantly reduce manufacturing costs.

Claims (1)

[Claims] 1. A phosphor bronze ingot consisting of 3 to 12 wt% Sn, 0.01 to 0.5 wt% P, and the balance Cu is hot worked at a processing rate of 10 to 30%, then cooled and heated again. A method of processing phosphor bronze characterized by subjecting it to hot working. 2. The method for processing phosphor bronze according to claim 1, characterized in that hot working is carried out at a temperature in the range of 600° to 800°C.