JPS59589B2 - Manufacturing method of clad plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a cladding material with good bondability and mechanical properties by simple production means.

When using metal materials, it is necessary to consider various properties such as tensile strength, corrosion resistance, conductivity, and weight, and select a material that has the optimal characteristics for each application and usage environment. .

However, it is often not possible to completely satisfy these complex requirements with a single metal or alloy, and there are many fields in which these requirements are met by using a cladding material that is a combination of different metals. For example, by using copper, which has excellent tensile strength, as the base material and a nickel-chromium alloy, which has excellent corrosion resistance, as the surface material, you can create a material that has both excellent corrosion resistance and tensile strength, by utilizing the advantages of art materials in the right place. Obtainable.
As examples of combinations of cladding materials, there are many other known combinations, too many to list. Explosion bonding, gas welding, diffusion rolling welding, etc. are known methods for manufacturing such cladding materials, but each method has advantages and disadvantages and has not yet reached a fully satisfactory state. .

In other words, in the explosive bonding method, materials are joined using explosive force, so it is necessary to pay sufficient attention to safety, which requires a large amount of equipment cost during production, and can only be handled by specially qualified personnel. This method is extremely restrictive, as it is not possible to do so, and there are also pollution problems caused by explosion noise and vibrations. In addition, in the gas welding method, it is essential to maintain manufacturing conditions, especially to maintain a stable and uniform welding temperature on the entire cladding surface, but this condition cannot be maintained with large cladding plates, and it is difficult to obtain stable quality. It had the drawback of being difficult.
In addition, in the diffusion rolling method, which is considered the most common method, the bonding surfaces of the base material and the bonded material must be polished to prevent J, and powders or plates of Sn, Zn, Cu, etc. are used as diffusion promoters. Since the mating surfaces of the base material and the mating material are interposed or plated and then rolled, harmful intermetallic compounds may be formed on the joint surfaces depending on the rolling conditions and the purity of the interposed material.

That is, all of these three methods have complicated manufacturing processes and also have quality problems, and there has been a desire for a new method to replace them. The present invention has been made in view of this situation, and it is an object of the present invention to provide a method for producing high-quality cladding plates using the simplest possible means.

Therefore, the manufacturing method of the present invention is a method for manufacturing a clad plate composed of two metals with melting points different from each other by 50°C or higher, preferably 100°C or higher, and more preferably 200°C or higher, in which the higher melting point metal is The gist is that a laminate made of a metal with a low melting point is placed on top of the base material, the temperature is raised to an intermediate temperature between the melting point of the base material and the melting point of the laminate, and then it is cooled. We succeeded in manufacturing a clad plate with good bondability between the base material and the laminated material using simple manufacturing equipment and simple operations. That is, in completing the present invention, the present inventor believed that it was necessary to conduct various studies from a completely different perspective from conventional methods, and as a result of various studies to take advantage of the differences in physical properties of the base material and the composite material that are the target metals. The present invention was completed by focusing on the difference in melting point. That is, a metal with a higher melting point is used as a base material, and a metal with a lower melting point is placed on the base material as a laminate, and the temperature is set at a temperature where the metal with a lower melting point melts but the metal with a higher melting point does not. "Intermediate temperature" means any temperature between the two temperatures, not one point in the middle), melts only the low melting point metal and enters the high melting point metal structure that has been heated to near the melting point. It completes a strong bond between the two metals by diffusion and penetration. The material targeted by the present invention is not particularly limited as long as it has a melting point difference of 50°C or more, but when using steel parts as the base material, metals with a melting point 50°C or more lower than the melting point of iron, For example, naval brass (melting point 880-890°C), cupronickel (melting point 1120-1180°C), Arms Prones (melting point 1030-1060°C), etc. are used. If the melting point difference is less than 50° C., the base material as well as the laminated material will begin to soften and melt, making it impossible to achieve the object of the present invention. A preferable melting point difference is 100°C or more, and even more preferably a melting point difference of 200°C or more. The present invention will be explained below based on examples.

As shown in Figure 1 (ζFor example, general structural carbon steel (SS4l)
) is made of stainless steel (SUS3O4).
) is welded and installed. A laminating material 3 made of, for example, naval brass (C-4621) is placed on the upper surface of the base material 1.
The reducible flux 4 is then spread so that the laminated material 3 is covered. Examples of the reducing flux include metal carbonates, metal borates, fluorides, and the like alone or in mixtures. When used as a mixture, carbonate 50-70%, borate 10-25%, fluoride 1-1
The best prescription was 0%. These fluxes have the function of preventing the surface of the laminated material from being oxidized by heating, which will be described later, and also reduce or dissolve oxides and foreign substances adhering to the surfaces of the base material and the laminated material. It also plays a role in cleaning the water. Incidentally, if the heating is carried out in a substantially completely non-oxidizing atmosphere and the bare surface of the material is sufficiently cleaned, the above-mentioned scattering of the flux can be omitted. The components (hereinafter referred to as works) 5 having the above combination are charged into a heating furnace 6 as shown in FIG. The heating furnace 6 generally uses city gas or the like as a heating source, and the workpiece 5 is placed on supporting bricks 8 on the furnace body 7, and after loading, the shutter 9 is closed and the furnace is sealed. Increase temperature.
When raising the temperature, it is preferable to raise the temperature gradually in order to make the temperature inside the furnace uniform.For example, it takes 120 minutes to raise the temperature to the target temperature. ~1560℃, so in this example 10
The target temperature was 50 to 1100°C. Note that if the heating temperature increases to exceed 1100°C, the rate of diffusion of iron, which is the base material, into naval brass will increase, so it is preferable to set the target temperature to 1100°C or less. The temperature is then maintained for 15 minutes to complete heating. After heating is completed, use a fork 10 to heat the furnace 6.
The workpiece 5 is taken out, and carbonization agent 11 is sprinkled as a heat insulating material onto the molten laminated material 8a to cover the entire surface of the laminated material, and then transferred to the cooling water tank 12. When carrying out the cooling process, the bottom surface of the base material 1 is set to match the cooling water level as shown in Figure 3, and the cooling water 13 is jetted from the bottom of the water tank 12 toward the center of the base material bottom surface. The workpiece 5 is cooled by contacting it. Water exceeding the set water level of the water tank is discharged from the tank flow weir 14 to the outside of the system. In the cooling system shown in Fig. 3, the molten composite material 3a is cooled from near the center, so solidification starts from the center and solidifies sequentially toward the periphery, so shrinkage during solidification is dispersed to the periphery. However, the thickness of the peripheral portion, which is thicker due to surface tension, becomes thinner by that amount, and the overall thickness becomes almost uniform. The solidified workpiece 5 is taken out from the water tank, the frame material at the peripheral edge is removed, and the end portion containing the sinker is cut using a lathe or the like to form a final product. Although the above embodiment method has been explained by taking up the combination of naval brass and general structural carbon steel, it is natural that the manufacturing conditions, especially the temperature conditions, will differ depending on the type of metal selected as the laminated material and the base material.

When the tensile strength and elongation of the Tallard plates manufactured as described above were measured, the results shown in Table 1 were obtained.

As shown in Table 1, the tensile strength and elongation of the clad plate produced by the method of the present invention fully satisfy the standard values for the base material alone and the laminated material alone, respectively, and the strength is improved by bonding the base material and the laminated material. No deterioration will occur.

Next, the shear strength was measured according to the procedure shown in FIGS. 4A, b, and c.

As shown in Fig. 4b, the width W (
Scrape off leaving only 1.5 times the thickness h of the mating material, and
The points at which the laminated material 3b breaks were determined by holding it between the jigs 15 and 15a shown in Figure e and applying a load from above, resulting in the results shown in Table 2. As shown in Table 2, the shear strength of the clad plates produced by the method of the present invention all show fully satisfactory results.

Furthermore, the bending characteristics are as follows: Specifically, in the case of front bending, back bending, and side bending, R = 2T (T: thick plate), and in the case of back bending, R = 2T (T: thick plate).
= 1.5T. The test results are shown in Reference Photos 1, 2, and 3, and there were no scratches or other defects on the outside of the curved part, indicating that the bonding strength between the laminated material and the base material was sufficiently high. It could be confirmed. Since the method of the present invention is constructed as described above, a cladding material having the desired shape can be manufactured all at once by welding the laminated material to the base material that has been finished into approximately the desired shape. Furthermore, since the laminating material sufficiently diffuses and permeates into the base material, the bond between the two materials becomes sufficiently strong. Unlike the diffusion rolling method, no insert material is required, so there is no generation of harmful intermetallic compounds on the joint surfaces, and a high-quality cladding material with particularly excellent uniformity of the joint surfaces can be obtained.

[Brief explanation of the drawing]

Figures 1, 2, and 3 are explanatory diagrams showing the procedure of an embodiment according to the present invention, in particular, Figure 1 is an explanatory diagram of a workpiece part, Figure 2 is a heating furnace part, and Figure 3 is an explanatory diagram of a cooling tank part. FIG. 4 is an explanatory diagram of a shear test method for the clad plate mating material.

Claims (1)

[Scope of Claims] 1. A method for producing a cladding plate composed of two metals having melting points different by 50°C or more, wherein a high melting point metal is used as a base material, and a low melting point metal is formed on the upper surface of the base material. 1. A method for manufacturing a clad plate, which comprises: placing a laminated material, raising and maintaining the temperature at an intermediate temperature between the melting point of the base material and the melting point of the laminating material, and then cooling. 2. The method for manufacturing a clad plate according to claim 1, which is carried out by encapsulating a reducing flux on the laminated material before the temperature is raised. 3. The method for manufacturing a clad plate according to claim 1 or 2, which comprises providing a frame material around the periphery of the base material and the laminated material. 4. Claim 3 in which the frame material is made of a metal that has a melting point higher than the holding temperature and is not subject to diffusion and penetration by the laminating material.
The method for manufacturing the clad plate described in Section 1. 5. A method for manufacturing a clad plate according to any one of claims 1 to 4, which is carried out by encapsulating a heat insulating agent on the upper surface of the laminated material before cooling. 6. The method for manufacturing a clad plate according to any one of claims 1 to 5, wherein the heat absorption point is set as one point in the center of the bottom surface of the base material. 7. The clad plate according to any one of claims 1 to 6, wherein the high melting point metal is general structural carbon steel, and the low melting point metal is one selected from naval brass, Cypronickel, and Arms bronze. Production method.