JPS5877785A - Production of rolled clad steel of copper or copper alloy - Google Patents

Abstract

PURPOSE:To produce rolled clad steel having excellent joining strength with low rolling reduction in the stage of producing a clad material of copper or a copper alloy and steel by controlling the surface temp. of the steel base material and the central temp. of the cladding metal of copper at specific temps. in rolling these materials. CONSTITUTION:In the stage of producing rolled clad steel of copper or a copper alloy and steel, copper or copper alloy plates 4 as 2 sheets of cladding metals are brought into contact with the inner sides of steel plates 2 which are base materials via release agents. Packing materials 8 are packed in the end parts to form these into sandwich construction. Or a dummy material 10, a release material 6, a cladding metal 4 and a base material 2 are formed in a laminar state to a composite slab, and such slag is rolled to produce clad steel. In this time, the materials are rolled by controlling temps. in such a way that the surface temp. of the dummy material 10 is kept lower by >=100 deg.C than the temp. of the metal 4 and that the central temp. of the metal 4 has a temp. difference within 300 deg.C from the m.p. thereof. The copper clad steel having excellent joining strength is produced with low rolling force.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing rolled clad steel of copper or copper alloy, and more particularly to a method for manufacturing rolled clad steel that can obtain good joint stiffness under low rolling pressure.

Conventionally, the main methods for manufacturing clad steel include rolling, explosive bonding, and sensual methods, each of which has its own advantages and disadvantages. Particularly, when using the rolling method, it is possible to control the quantity of wide and long steel plates, and there are advantages such as no work hardening of joints, but on the other hand, the thickness of the assembled slab before rolling is Since the plate thickness and rolling reduction ratio are the same, extremely thick clad steel is required when a large rolling ratio is required as in the conventional rolling method, which has the drawback of being extremely difficult to manufacture.

In addition, in the manufacturing method of clad steel by the rolling method, the cleanliness of the rolling surface, rolling reduction ratio, rolling pressure, and rolling temperature are the main factors that affect the progress of crimping. In the prior art, only the cleanliness of the bonding surface has been the focus of attention, and has been the subject of debate among woodcutter experts.

In other words, from the method of plating the joint surfaces,
A variety of methods have been studied, including the method of maintaining the interior of an assembled composite slab as disclosed in No. 100890, but many of these manufacturing methods require complicated labor and do not require high manufacturing costs. It was something to do.

The purpose of the present invention is to solve the above-mentioned labor problems of the prior art.

The object of the present invention is to provide a method for manufacturing piezoelectrically coupled copper or steel alloy steel that does not require special complicated equipment.

The assembled composite slab used in the production of piezoelectric steel is
As shown in FIG. 1(A), two sheets of laminating material 4 are in contact with the inside of base material 2 on both sides with a release material 6 sandwiched between them, and the ends are filled with filler material 8. , Figure 2 (B)
K Dummy material 10 as shown. 7 to form layers of release material 6, laminate material 4, and base material 2? ? There is a German cheesy thing.

As mentioned above, in the two-way rolling method, there are factors such as rolling reduction ratio, rolling pressure, and rolling temperature that affect crimping, but rolling pressure and degree of rolling are contradictory factors, so it is possible to simultaneously benefit both of them. It would be very warm for the country to move in that direction. That is, as the rolling temperature increases, the deformation resistance of the rolled slab itself becomes smaller and the rolling pressure decreases. Conversely, in order to increase the deformation resistance in order to increase the rolling pressure, the rolling temperature must be lowered. rolling pressure.

By keeping the rolling temperature at a rolling temperature and allowing compression to progress effectively, it is possible to lower the lower limit reduction ratio, which also serves as a manufacturing cap. Further, although the strong reduction rolling method can increase the rolling pressure, it does not lower the rolling ratio, which is the initial objective.

The Ministry of the Invention and others have deeply studied the factors of crimping, and found that the rolling pressure, 1 Am degree, is limited to "at the joint surface".
It was found that there is no need to maintain the rolling temperature of the entire assembled slab at a high temperature, but it is sufficient to maintain the temperature of the interface to be joined at a high temperature. In other words, it has been found that the overall rolling pressure can be increased by lowering only the temperature of the surface layer of the assembled composite slab without significantly lowering the temperature of the joint interface.

The gist of the present invention is as stated above.

In other words, the pressure jf, t is obtained by assembling a composite slab in the form of a complete sandwich or a semi-sand inch using a single plate as the base material and a sea bream or steel composite plate as the stiffening material.
i! In a clad steel knitting method for copper or steel alloy, the structural surface m length of the base material or dummy material is set to be at least 100°C lower than the temperature of the laminate material, and the center temperature of the laminate material is lower than the temperature of the laminate material. This is a method for producing clad steel made of sea bream or copper alloy, characterized in that piezoelectricity is started at a point where there is a temperature difference of 300° C. or more from one point.

The method of increasing the temperature difference between the surface layer and the center of the assembled composite slab is not particularly limited in this project, but there is a method of forcibly cooling the surface layer, or a method of forcibly cooling the surface layer, or a method of increasing the temperature difference between the surface layer and the center. Possible methods include cooling. By lowering only the temperature of the surface layer portion, the rolling pressure can be increased without significantly lowering the temperature at the bonding surface between the base material and the laminate.

In order to effectively carry out the rolling of the present invention, the surface of the base material or f-material of the assembled composite slab needs to be at least 100°C lower than the temperature of the laminated material; This is because if the difference is less than 100°C, the rolling pressure will not increase sufficiently and good bonding strength will not be obtained.

In addition, the center rolling start temperature of the laminate was set to a temperature difference within 300°C from the melting point of the steel or copper alloy used as the laminate, in order to ensure the rolling temperature, which is another factor in crimping. This is because if the temperature difference from the melting point exceeds 300°C, sufficient joint stiffness cannot be obtained under low pressure.

The present invention was able to obtain good joint strength under low pressure by lowering only the surface temperature of the assembled composite slab and limiting the center temperature.

Example: Hot-rolled 90% Cu-19% Nl cupronickel (each piece 1150C) with a thickness of 15 cm was used as a laminating material, and a plate with a thickness of 6
A complete sandwich-like assembled composite strip with a total thickness of 160 cm using JISSM41B of 5 cm as a base material was rolled by the conventional method and the method of the present invention under the conditions shown in Table 1.Assembled composite strip at the start of rolling 41 The difference between the surface temperature of the plate and the temperature of the laminate was 50°C in the conventional method, but in the method of the present invention, the difference in the center temperature was 1°C.
When rolling was started after cooling from 000'C to 900'CK, the temperature difference expanded to 200°C. Figure 2 shows the results of measuring the rolling load during rolling, and the method of the present invention has a lower temperature difference than the conventional method. It has a high rolling charge.

The results of the investigation of rolled Kigug P nickel clad steel are the first
As shown in the table, the joint area ratio is 8&3% in the method of the present invention, compared to 7.3% in the conventional method, and the cooling effect is recognized. In addition, the shear test results for the joints are all JIS
The result was much higher than the standard 10kg/-.
This shows that the disadvantageous factor of temperature reduction due to cooling from 0°C to 900°C is outweighed by the advantageous factors of the method of the present invention.

As is clear from the above examples, the method of the present invention
I'fjJIII! If rolling is started by setting It to 100°C or more lower than the temperature of the laminate and limiting the center temperature of the laminate, it is possible to produce rolled clad steel with good joint strength at a low reduction ratio. Ta.

The present 5Ii81i method can be widely applied not only to copper or copper alloys but also to the production of non-ferrous alloys and clad steels such as special purpose steels.

[Brief explanation of drawings]

FIG. 1(A) is a cross-sectional view showing a complete sandwich-like assembled composite slab, FIG. 1(B) is a cross-sectional view showing a semi-sandwich-like assembled composite slab, and FIG. 2 is a cross-sectional view showing a conventional method and the present invention method. It is a diagram showing rolling load during rolling. 2... Base material 4... Laminated material 1 G-... Dada material agent Takeo Nakaji

Claims (1)

[Claims] In a method for producing clad steel of steel or copper alloy, which is piezoelectrically bonded from a 1 ktt German bridge-like assembled composite slab using a completely sandwiched structure or a structure material, the surface temperature of the base material or the structure material is adjusted to the above-mentioned level. Clad steel production of copper or steel alloy, characterized in that the temperature is 100°C or more lower than the temperature of the material, and rolling is started when the center temperature of the laminate is within 300C of the melting point of the laminate. Method.