JPS63238986A - Manufacture of composite material with deformed cross section - Google Patents

Abstract

PURPOSE:To form composite material with a deformed cross section by inserting a core material into outer material and drawing these to form fitting material and hot-rolling it by an inclined rolling mill to form the composite material with the circular cross section and cooling the composite material. CONSTITUTION:The core material 2 is inserted into the outer material 3 and cold-drawn by a drawing machine and the core material 2 is stuck fast to the outer material 3 without a gap to form the cylindrical fitting material 4. The fitting material 4 is heated with a heating furnace. The fitting material 4 of the heated material is rolled by the rolling mill 10 and made to the composite material 5 with the circular cross section having the prescribed outside diameter dimensions. At the time of rolling the composite material 5 by the inclined rolling mill 10 after cooling it, in order to remove scales of the external surface, the material 5 is cut by a centerless grinder, etc., and then, rolled by a square roll rolling mill, for instance, and its cross-sectional shape is formed to a rectangle and the composite material 1 with the rectangular cross section is formed. Accordingly, the composite material with the deformed cross section with the satisfactory quality can be manufactured with the high productive efficiency.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to stainless steel clad copper rods, titanium clad copper rods, etc. used as power supply rods in electrolytic cells, for example.
The present invention relates to a method of manufacturing a composite material with a narrow irregular cross section by fitting an outer layer material on the outside of a core material.

[Prior art] Power supply rods used in electrolytic cells containing salt are required to have vehicle weight conductivity and corrosion resistance against alkali, so copper, which is a vehicle weight conductive material, must be used alone. Composite materials such as stainless steel clad copper rods or titanium craft copper rods are used, which are made by fitting an outer layer material of stainless steel or titanium with excellent corrosion resistance onto the outside of a core copper rod.

As a method for producing such composite materials, methods using hot isostatic extrusion (Japanese Patent Publication No. 54-8188, Japanese Patent Application Laid-Open No. 61-4
No. 2416), in which a cylindrical outer layer material is fitted on the outside of a cylindrical core material to form a fitting material, and lid plates are provided at both ends in the axial direction of the fitting material to cover this. This is a method of forming a composite material by providing a composite material and restraining the relative movement between the core material and the outer layer material, and then stretching the fitting material using a hydrostatic extrusion method to join the core material and the outer layer material. .

However, this method has the disadvantage that if the deformation resistance of the core material and the outer layer material are significantly different, such as the above-mentioned stainless steel craft copper rod, extrusion molding becomes impossible, and the selection range of the core material and outer layer material is narrow. Moreover, before forming the fitting material, it is necessary to process the outer circumferential surface of the core material and the inner circumferential surface of the outer layer material with high precision, and furthermore, after the extrusion is completed,
It is necessary to remove lubricant adhering to the outer surface of the composite material, etc.
There were disadvantages in that pre-treatment and post-treatment required a large amount of time and productivity was low.

Therefore, the present inventors have proposed a method for manufacturing composite materials that solves the above-mentioned difficulties by using an inclined roll rolling mill for manufacturing composite materials (Japanese Patent Application No. 61-272580 and Japanese Patent Application No. 61-1989
No. 181635).

[Problem that the invention seeks to solve]

Now, the power supply rod, which is a typical composite material such as the stainless steel craft copper rod or the titanium clad copper rod, is used by combining a plurality of these to form a flat electric excavation in an electrolytic cell.

This electrode is made by arranging the power supply rods having a circular cross section in parallel on one plane, and welding a member made of the same material as the outer layer agent to one end of these in contact with the solution to integrate them into a flat plate. However, the power supply rod has a circular cross section,
Since there is a line contact with the connecting member, there is a problem that it is difficult to construct an electrode having sufficient strength, and in order to solve this problem, a power supply rod having a rectangular cross section is desperately needed.

However, although the above-mentioned methods of Japanese Patent Application No. 61-272580 and Japanese Patent Application Laid-open No. 61-181635 can produce composite materials with a circular cross section with high efficiency, they are difficult to manufacture composite materials with a rectangular cross section. cannot be accepted, while
The hot isostatic extrusion method described above can be applied to the production of composite materials with a rectangular surface by using a forming die with a rectangular die hole, but this method has the above-mentioned drawbacks and can be applied to the production of composite materials with a rectangular surface. It cannot be used to manufacture craft copper rods, and it is difficult to remove scale attached to the outer circumferential surface of the rectangular composite material after extrusion, as it is difficult to do this by mechanical cutting and requires manual labor. This inevitably led to a further decline in productivity.

The present invention has been made in view of the above circumstances, and can be applied not only to the production of composite materials having a rectangular cross section, but also to composite materials having an irregular cross section, that is, a cross sectional shape other than a circle, and can be manufactured with high production efficiency. An object of the present invention is to provide a method for manufacturing a composite material with a modified cross section.

[Means for solving problems]

A method for manufacturing a composite material with an irregular cross section according to the present invention is a method for manufacturing a composite material with an irregular cross section in which an outer layer material is fitted on the outside of a rod-shaped core material having an irregular cross section. After degreasing and cleaning the inner surface of the cylindrical outer layer material, which has a higher deformation resistance, the core material is inserted into the outer layer material, and they are brought into close contact by cold drawing to form a cylindrical fit. After heating the fitting material to a predetermined temperature lower than the respective melting points of the core material, the outer layer material, and the intermetallic compound formed between them, three or more cone shapes are formed. Consisting of a second step of rolling with an inclined rolling mill equipped with rolls to obtain a circular cross-section composite material, and a third step of cooling the composite material and then forming it into a modified cross-section to obtain a modified cross-section composite material. It is characterized by

[Effect]

In the present invention, after the core material is inserted into the outer layer material, this is drawn to form a fitting material, which is hot rolled using an inclined rolling mill to form a circular cross-section composite material. At this point, the scale on the outer peripheral surface is removed, and the circular cross-section composite material is cold-formed into a modified cross-section to obtain a modified cross-section composite material.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on drawings showing embodiments thereof. Figure 1 shows how to manufacture a composite material with a rectangular cross-sectional shape.
It is a process diagram when the manufacturing method of the irregular cross-section composite material based on this invention (hereinafter referred to as the method of this invention) is used.

For example, when manufacturing a stainless steel clamped copper rod, the outer circumferential surface is machined, for example, to remove surface scale, and the cylindrical copper core material 2 and its inner circumferential surface are pickled. First, the outer circumferential surface of the core material 2 and the inner circumferential surface of the outer layer material 3 are degreased and cleaned with acetone or the like, respectively, and then the outer layer material 3 is made of a stainless steel pipe. Insert the core material 2 into the inside of the (first
(see Figure (C)), then cold drawing is performed using a drawing machine (not shown) to bring the core material 2 and the outer layer material 3 into close contact with each other without any gaps,
The first step is completed by forming a cylindrical fitting material 4 (see Fig. 1 (dl)). In this first step, when inserting the core material 2 into the outer layer material 3, Although it is necessary to process, since both are brought into close contact by deformation of the outer layer material 3 by the cold drawing, the process does not require strict tolerances.Also, by the cold drawing, The core material 2 and the outer layer material 3 are brought into close contact with each other without any gaps to form the fitting material 4. When the fitting material 4 is heated in a second step to be described later, the core material 2 and the outer layer material 3 are heated. Oxides that reduce bonding strength are not generated at the interface between the two.

The fitting material 4 formed in the first step is then heated in a heating furnace (not shown). This heating is performed to create a diffusion layer between the core material 2 and the outer layer material 3 and to bond them together. When either the outer layer material 3 or the intermetallic compound generated between the two melts,
When this core material 2. The temperature is limited to a temperature lower than the respective melting points of the outer layer material 3 and the intermetallic compound. For example, in the production of stainless steel clad copper rods, taking into consideration that the stainless steel used as the outer layer material 3 has poor workability at low temperatures, the melting temperature of the copper with the lowest melting point used as the core material 2 starts from 1030°C to 1040°C.
It is desirable to heat to a temperature as close to 1020°C as possible.

The heated fitting material 4 is then fed to a later-described inclined rolling mill 1o equipped with, for example, three cone-shaped rolls, and rolled in the rolling mill 10 into a circular cross section having a predetermined outer diameter. The composite material 5 is obtained (see Fig. 1 (el)), and the second step is completed. In this rolling, the reason for using an inclined rolling mill with cone-shaped rolls and the limitation of the number of rolls in the rolling mill to 3 or more. The reason is to manufacture a composite material with high bonding strength and excellent bondability, as detailed in Japanese Patent Application No. 61-272580 proposed by the present inventors. In the production of copper rods, there is a risk that cracks may occur in the outer layer material 3 during rolling by the inclined rolling mill 10 due to the copper that diffuses into the stainless steel outer layer material 3 due to the heating in the heating furnace. Therefore, as shown in the above-mentioned Japanese Patent Application No. 61-272580, when inserting the core material 2 into the outer layer material 3 in the first step, nickel, which has good diffusibility into both copper and stainless steel, is used. In order to interpose the layer between the core material 2 and the outer layer material 3, a nickel foil having a thickness of about 40μ is wound around the outer peripheral surface of the core material 2, or the outer peripheral surface of the core material 2 or the outer layer material Nickel plating is applied to the inner peripheral surface of 3 to prevent copper from diffusing into the stainless steel.

The circular cross-section composite material 5 formed in the second step is
After cooling, the scale generated on the outer surface during rolling by the inclined rolling mill 10 is removed (it is cut or cut by a centerless grinder or lathe, and then, for example, the 40,000 roll rolling mill 20 described below is applied. is rolled and formed into a rectangular cross-sectional shape to form a rectangular cross-sectional composite material (first
The method of forming the zero-circular cross-section composite material 5 into the rectangular cross-section composite material 1 at the end of the third step is not limited to rolling with the 40,000-roll rolling mill 20 (see figure ``)''). Drawing using a die or roller die having die holes of The scale may be removed by pickling or shot processing the material 5.

FIG. 2 is a schematic front view from the upstream side in the moving direction of the fitting material 4 of the inclined rolling mill 10 used to roll the fitting material 4 in the second step, and FIG. FIG. 4 is a side sectional view taken along the line ■-■ in the figure, and FIG. 4 is a view taken along the line rV-IV in FIG. 2 for explaining the inclination angle β of the inclined rolling mill 10.

The inclined rolling mill 10 has an inlet part 11b on both sides of a gorge part 11a, which is shaped like a truncated cone and whose diameter decreases as it reaches the end, and an outlet part which has a short truncated cone shape and whose diameter slightly increases as it reaches the end. This is a 30-mill rolling mill having three inclined rolls 11.11.11 having a cone shape as a whole and each having a cone-shaped section, each inclined roll 11.11.11 having an entrance surface 11b for rolling material. With the fitting member 4 facing upstream in the moving direction (hereinafter referred to as the front side), the rotating shaft 1 is
The intersection point 0 (roll setting center) between the center line Y-Y of 2 and the plane including the gorge portion 11a is the same point whose center is on the pass line XX of the fitting material 4, which is the rolled material, and perpendicular thereto. They are arranged at equal intervals on the circumference. Said center line Y-
As shown in FIG. 3, Y is inclined with respect to the pass line XX by a predetermined crossing angle γ with the front portion facing downward, and as shown in FIGS. The fitting material 4 is inclined by a predetermined oblique angle β in the circumferential direction, and each inclined roll 11, 11.11 -Y, they are driven to rotate in the same direction and synchronously with each other, as shown by arrows in FIG. 2, by a driving force from a driving source (not shown).

As described above, the fitting material 4 is heated to a predetermined temperature in the heating furnace and fed to the inclined rolling mill 10.
A tilted roll 11.11.1 that is bitten between the entrance surfaces 11b, llb, and llb with its axis aligned with the pass line XX, and rotates with an inclination angle β.
1, as shown by the white arrow in FIG. 3, while being spirally moved along the pass line A high pressure of 80 to 90% is applied, and the rolled portion is gradually reduced in diameter into a truncated cone shape, forming the gorge portions 11a, lla, l.
After passing between the la and exit surfaces 11c, llc, llc, the circular cross-section composite material 5 has a predetermined outer diameter. In this way, in the inclined rolling mill 10, while the fitting material 4 rotates once in its axial center layer in accordance with the rotation of the inclined rolls 11, 11.11, each of the - After applying pressure twice, the fitting material 4 forms the gorge portions 11a and 11a.

Until reaching 11a, the diameter reduction is performed by repeating the rolling intermittently, and since the amount of deformation that the fitting material 4 undergoes due to - times of rolling is small, the fitting material 4 is formed into a circular cross-section composite material 5. Even if a large diameter reduction is required to make the core material 2, it can be easily formed without cracking, etc.
and the outer layer material 3 can be reliably integrated.

By the way, when rolling is performed using the inclined rolling mill 10 in order to obtain a circular cross-section composite material 5 from the fitting material 4, in which the deformation resistance of the outer layer material 3 is smaller than that of the core material 2, the amount of deformation of the outer layer material 3 is , is larger than that of the core material 2, and the outer layer material 3 is greatly thinned and its circumference becomes longer, resulting in so-called flaring, which protrudes between the rolls 11, 11, 11 during rolling. During the heating step, the diffusion layer formed between the core material 2 and the outer layer material 3 peels off, so the method of the present invention cannot be applied to the production of the above-mentioned composite material.

However, in most composite materials, the deformation resistance of the outer layer material 3 is greater than that of the core material 2 due to its usage, and the above-mentioned gas point does not narrow the scope of application of the method of the present invention.

After removing the scale generated on the outer surface of the circular cross-section composite material 5 thus formed, as described above,
In order to obtain a rectangular cross-section composite material 1, the 40,000 roll rolling mill 2
0. FIG. 5 is a partially cutaway pressure surface view of the 40,000-roll rolling mill 20 as seen from the feeding direction of the circular cross-section composite material 5 as a rolled material.

Four rolls 21, 21.2 of a four-way rolling mill 20
1°21 has a short cylindrical shape and has a hexagonal front shape as shown in this figure. Intersection of the plane and the path line (path center)
They are rotatably supported on respective axis layers that are spaced apart from Z by an equal distance and are perpendicular to each other, and between these outer circumferential surfaces that face each other with the path center Z as the center, a molding result is obtained. A rectangular opening 23 corresponding to the outer dimensions of the rectangular cross-section composite material 1 is formed. A pair of bevel gears 24 , 24 are mounted on both sides of each roll 21 in the axial direction with their respective tooth forming surfaces facing outward so as to rotate together concentrically with the respective rolls 21 . Said roll 2
1, 21, 21, 21, the other end of a drive shaft 25 whose one end is connected to a drive source (not shown) is attached to the roll 21 and this by its rotation. It is inserted to rotate the bevel gear 24.24. Accordingly, the rolls 21, 21, 21.21 are rotated in accordance with the rotation of the drive shaft 25, respectively, by means of the bevel gear 24.24 meshing between the adjacent rolls 21.21. They are rotated synchronously and at the same speed in the direction shown by the arrows.

The circular cross-section composite material 5 obtained in the second step and fed to the 40,000-roll rolling mill 20 has its axis aligned with the bus center Z, and is placed on the front side of the paper in FIG. is inserted into the opening 23, and while passing through the opening 23, the rolling blades applied from four sides by the rolls 21, 21, 21, 21 form a rectangular cross section corresponding to the shape and dimensions of the opening 23. A composite material 1 having a rectangular cross section is formed.

Finally, a description will be given of an example in which a titanium clad copper rod and a stainless steel clad copper rod were manufactured by the method of the present invention, and the bonding state of the core material and outer layer material therein was inspected.

(Example 1) JIS Cl100 tough pitch copper with an outer diameter of 49.5 m
m, a round bar-shaped core material 2 obtained by machining to a tolerance of ±0.1 mm+, and JIS Class 2 pure titanium having an outer diameter of 57a+n+ were machined to an inner diameter of 51 mm and a tolerance of ±0.1 mm. After degreasing and cleaning the obtained cylindrical outer layer material 3 and inserting the core material 2 into the outer layer material 3, cold drawing is performed to obtain a fitting material 4 having an outer diameter of 55+u+. went.

Next, this was heated in a heating furnace for approximately 1 hour to a temperature of 750℃.
℃, circular cross-section composite material 5 with an outer diameter of 3011I11
In order to obtain the gradient pressure t! shown in FIGS. 2 to 4, tffl
Hot rolling was carried out at IO. The specifications of the inclined rolling mill 10 are as follows.

Roll crossing angle γ 5 @ Roll inclination angle β 13° Roll diameter 180 arm Roll material SCM 440 Roll rotation speed 10 Orpm Next, the outer peripheral surface of the circular cross-section composite material 5 obtained by hot rolling was placed in a centerless grinder. After grinding to 0.41 and removing the surface scale, a four-way rolling mill 2 equipped with four rolls made of 345C with an outer diameter of 180 mm was used.
Cold rolled at 0, medium 25 x 25 and medium 31
Titanium-clad copper rods of rectangular cross-section with two cross-sectional dimensions of x24 were manufactured.

The bonding interface between the core material and the outer layer material in the titanium clad copper rod manufactured in this way was examined using a scanning electron microscope (SE
M) and electronic probe microanalyzer (EPMA)
As a result of both observation and ultrasonic flaw detection,
In both of the above two types of titanium-clad copper rods, no peeling, oxides, or defects were observed at the bonding interface, and it was observed that diffusion had progressed sufficiently, and the gap between the core material and the outer layer material was observed to be sufficient. It became clear that the bonding condition was good. FIG. 6 is an SEM observation photograph of the vicinity of the bonding interface between titanium, which is the outer layer material, and copper, which is the core material.

(Example 2) JIS Cl100 tough pitch copper with an outer diameter of 49.5 m
Degrease the tip bar obtained by machining to a tolerance of ±0.1 m.

After cleaning, a core material 2 made by winding a nickel foil with a thickness of 40μ, which has also been degreased and cleaned, is wrapped around the outer periphery of the core material 2, which has an outer diameter of 60.5vw and a wall thickness of 3.5mm, as per JIS 5IJS3.
After inserting a 10S stainless steel pipe into the cleaned and cleaned outer layer material 3, cold drawing was performed to obtain a fitting material 4 with an outer diameter of 55Il111.Next, this was placed in a heating furnace. After heating to 1020°C, the inclined rolling mill lO explained in the manufacturing example of the titanium clad copper bar was used.
Hot rolling was carried out to obtain a circular cross-section composite material 5 having an outer diameter of 30++ m. Next, the outer circumferential surface of this circular cross-section composite material 5 is ground by 0.4 mm using a centerless grinder to remove surface scale, and then the four-sided circular cross-section composite material 5 is ground using a centerless grinder to remove surface scale. Single rolling mill 2
Cold rolling was performed at 0 to produce a stainless steel craft copper bar with a rectangular cross section having a cross-sectional size of 25 x 25 mm.

Scanning electron microscopy shows the bonding interface between the core material and the outer layer material in the stainless steel clad copper rod manufactured in this way! *(
SEM) and electronic probe microanalyzer (EPM)
As a result of both observation using A) and ultrasonic flaw detection, no peeling, oxides, or defects were observed at the bonding interface, and it was observed that diffusion was sufficiently progressing.
It was found that the bond between the core material and the outer layer material was good, as in the case of manufacturing the titanium clad copper rod.

In this example, a case was explained in which a composite material having a rectangular cross-sectional shape was manufactured. However, when manufacturing a composite material having an irregular cross-section having a hexagonal, hexagonal, etc. It goes without saying that the method of the present invention can be applied by changing the rolling mill used or the die or roller die.

〔effect〕

As detailed above, in the method of the present invention, the core material and the outer layer material are brought into close contact with each other by drawing in the first step, so there is no need to pre-process them with high precision. Since a composite material with a circular cross section is formed by inter-rolling, a composite material with a high efficiency and good bonding state can be obtained.Furthermore, this circular cross-sectional composite material is formed into an irregular cross section in the subsequent third step. Since a composite material with an irregular cross section is thus obtained, excellent effects such as the ability to manufacture a composite material with a high quality irregular cross section at high production efficiency are achieved.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a process diagram of the method of the present invention, FIG. 2 is a front view of main parts of an inclined rolling mill used in the method of the present invention, and FIG. Figure 4 is a side cross-sectional view taken along line m-nt in Figure 4, and IV-I in Figure 2 shows the inclination angle β.
5 is a partially cutaway front view of a four-way rolling mill used in the method of the present invention, and FIG. 6 is a view of the vicinity of the bonding interface of a titanium-clad copper rod manufactured by the method of the present invention. S.E.
This is an M observation photograph. 1... Rectangular cross section composite material 2... Core material 3...
Outer layer material 4... Fitting material 5... Circular cross section composite material 10... Inclined rolling mill 20... Four-way roll rolling mill patent Applicant Sumitomo Metal Industries Co., Ltd. agent Patent attorney Kono Noboru Figure 2 IV Figure 3 Figure 4, υ zl Fu 5 Ward f Mejiri Figure 6

Claims (1)

[Scope of Claims] 1. A method for manufacturing a composite material with an irregular cross section, in which an outer layer material is fitted on the outside of a rod-shaped core material having an irregular cross section, which comprises: After degreasing and cleaning the inner surface of each of the large cylindrical outer layer materials, the core material is inserted into the outer layer material, and they are brought into close contact by cold drawing to obtain a cylindrical fitting material. and heating the fitting material to a predetermined temperature lower than the respective melting points of the core material, the outer layer material, and the intermetallic compound formed between them, and then heating the mating material to a predetermined temperature lower than the respective melting points of the core material, the outer layer material, and the intermetallic compound formed between them, and then heating the mating material to a predetermined temperature that is lower than the respective melting points of the core material, the outer layer material, and the intermetallic compound formed therebetween, and then heating the mating material to a predetermined temperature that is lower than the respective melting points of the core material, the outer layer material, and the intermetallic compound formed between them. The second step is to obtain a circular cross-section composite material by rolling with a rolling mill.
and a third step of cooling the composite material and then forming it into a modified cross-section to obtain a composite material with a modified cross-section.