JPS61115604A - Copper and copper alloy plate for press forming - Google Patents

Abstract

PURPOSE:To obtain a copper and copper alloy plate for press forming which is improved in formability and in the productivity and yield of press forming by roughening the surface of a rolling plate made of copper and copper alloy to some extent. CONSTITUTION:The rolling plate made of copper and copper alloy is rolled and the surface thereof is roughened in the following manner by, for example, a steel roll of which the surface is roughened by a means such as shot blasting: The surface is so roughened that the maximum peak-to-valley height (Rmax) of 1 inch length in at least the rolling direction of the above-described rolling plate and the direction perpendicular thereto is 3-10mum and that the number of peaks and valleys (PPI) having >=50mu inch height (depth) within 1 inch length is >=30 pieces. The formability such as bulging characteristic of the above- mentioned rolling plate made of the copper (alloy) is improved and the productivity and yield of press forming are thereby improved.

Description

DETAILED DESCRIPTION OF THE INVENTION F. INDUSTRIAL APPLICATION FIELD The present invention relates to a rolled plate for press forming made of copper and prepared alloy.

1 Prior Art 1 The rolled plate used for press forming has a mirror-like surface,
That is, those having a prite finished surface (B.C.) and those having a dull finished surface (D.C.) which is slightly rougher than the above-mentioned plyte finish but sufficiently flat are generally used. In this type of pressed FFI plate, attempts have been made to improve the material performance by adjusting the chemical composition of the alloy, which cannot withstand severe press forming, and by subjecting it to heat treatment.

However, in recent years, as the shapes of pressed products have become extremely complex, the processing conditions for press forming have become even more severe, and it is difficult to meet the severe processing conditions simply by improving material performance as described above. This is the actual situation. As a result, the productivity and yield of press molding are seriously reduced.

[Object of the invention] The present invention has been made in view of the above problems, and includes:
The purpose is to improve the formability of the rolled plate by adjusting the surface shape of the rolled plate without changing the material of the rolled plate or its composition, and to improve the productivity and V yield of press forming.

[Background of the Invention 1] The present inventor has developed a method by roughening the surface of a rolled material made of aluminum and an aluminum alloy.
The mechanical properties of the rolled plate, such as tensile strength, yield strength, and elongation, are not lowered compared to conventional B, C, and DC plates, and the formability, such as the elongation properties, of the rolled plate is significantly improved. I have already applied for a patent after gaining the knowledge that it improves the quality of vines.
-167159). Subsequently, similar effects were found for rolled plates made of copper and prepared alloys. Although it is not clear why forming processability is improved by roughening the surface of the rolled plate, it is speculated that it is because the lubricant becomes more likely to adhere to the surface of the rolled plate. Note that the evaluation criteria for the surface roughness of a rolled plate are the maximum roughness Rmax and P P
r (peak point p6inch) was adopted.

That is, as shown in the drawing, the maximum roughness Rrnax is defined as the difference in height between the highest peak Mo and the lowest valley Vo within a length of 1 inch of the rolled plate, while PPI is defined as the height difference in the above 1.
The number of peaks MSM, .
It is defined as the sum of the number of valleys v, ■, . . . , ■ having a depth of inches or more.

In the tests conducted by the present inventor, RIIaX was
When the PPI is set in the range of 3 μm and PPI is set to 30 or more, good stretchability and bending workability are obtained, and the mechanical properties mentioned above do not deteriorate compared to conventional B and C plates and DC1. The result was obtained.

That is, Rwax is less than 3 μm, or PP [is 3
If Rwax is less than 0, the stretchability and bending workability of the rolled plate will not improve at all. On the other hand, if Rwax exceeds 13 μm, although good bending workability can be obtained, the stretchability and mechanical physical properties have decreased. In addition, when the PPI exceeds 200 pieces, extremely good stretchability and bending workability can be obtained, but it is difficult to actually set the PPI above 200 pieces due to the current production equipment. Even if the number of PPIs can be set to more than 1, it is difficult to achieve sufficient mass productivity, so it is preferable to set the PPI in the range of 30 to 200.

(: Also, Rraax and PII are within the above setting range within 1 inch length in all directions of the rolled plate, that is, each peak (or valley) is However, from the viewpoint of ease of measurement of Rmax and PPI and mass production of rolled plates, the above settings are applied in at least two directions, that is, in parallel and perpendicular to the rolling direction. It is considered good if it falls within the range.

The methods for roughening a rolled sheet include 1) rolling with a rolling roll whose surface has been roughened and transferring the rough surface shape of the roll surface to the rolled material; (2) chemical treatment after rolling ( Etching, etc.) or electrochemical treatment may be considered, but method (ii) increases the number of steps and costs, and is therefore disadvantageous in practice.

[Structure 1 of the Invention] Based on the above-mentioned findings, the present invention provides rolling with a rolling roll with a roughened surface, at least a maximum set Rmax within a length of 1 inch in directions parallel and perpendicular to the rolling direction. 3~
13μm, and 50μ within the above 1 inch length
Number of peaks and valleys with a height or depth of inches or more P
It is an object of the present invention to provide a copper and copper alloy plate for press forming, the surface roughness of which is adjusted by the above-mentioned rolling rolls so that the number of PI is 30 or more.

For example, a steel roll can be used as the above-mentioned rolling roll, and the surface of the steel roll is roughened by means such as shintoplast or electrical discharge machining.

In addition, when rolling a rolled plate, for example, in the case of a rolled plate made of prepared alloy, one-pass rolling is preferable depending on the type of roll, and it is also possible to roll the plate multiple times if necessary.

[Example 1] As a representative example of the present invention, for a rolled plate (thickness: 1.0m+*) made of brass (70% copper: 30% zinc), the R end ax,
The results of measuring PPI, mechanical properties, and extensibility are shown in the table on the next page.

Note: Made of brass, plate thickness = 1-1σB: tensile strength, σo, 2: proof stress, δ: elongation Invention material No. 1-10 in the same table has RIIax and PPT within the setting range of the present invention (R+*ax: It is rolled by rolling rolls having various rough surface shapes so as to fit into a 3 to 13 micron ring, PPI: 30 or more pieces.

Also, in the same table, rolled sheets in which either or both of R+*ax and PPI are out of the setting range of the present invention are shown as comparison material No. 1.
~7 is shown. Among these, comparative material No. 1 was rolled with rolling rolls for B and C, and comparative material No. 2 was rolled with rolling rolls for beam and C.

σB in the same table is tensile strength, σ. , 2 is proof stress, that is, 0.
The stress at which 2% permanent elongation occurs, δ, is the elongation, and the efuserin value is used as an evaluation standard for extensibility.
As this value increases, the overhang property increases.

As is clear from the table, the mechanical properties of the invented material are approximately the same as those of the comparative material, and the stretchability is considerably improved.

This tendency was also the same for copper alloys other than brass and copper rolled plates.

[Effects of the Invention] As explained above, in the present invention, the surface of the rolled plate made of copper and prepared alloy is roughened to some extent (specifically, R
IIax is 3 to 13 microns, PPI is 30 or more), the forming processability such as the stretchability of the rolled plate can be improved, and thereby the productivity and yield of press forming can be improved.

[Brief explanation of drawings]

The drawing is an enlarged schematic view showing the surface shape of the rolled plate. M...Mountain, ■...Valley.

Claims (1)

[Claims] (1) The surface is rolled with a roughened rolling roll, and the maximum roughness (Rmax) within a length of 1 inch in directions parallel and perpendicular to the rolling direction is 3 to 13 μm, and the above 1 inch The surface roughness is adjusted by the rolling roll so that the number of peaks and valleys (PPI) having a height or depth of 50 μinch or more within the length of the roll is 30 or more. Copper and copper alloy plates for press forming.