JPH04118185A - Clad rolling method - Google Patents

Abstract

PURPOSE:To easily produce a three-layered clad by rapidly heating respective cladding metals with IR rays from the surfaces of the cladding metals while the respective cladding metals are held in proximate to the front and rear surfaces of a core material, then passing the cladding metals through rolling rolls, thereby press welding the cladding metals. CONSTITUTION:The cladding metals 5, 6 are disposed near the front and rear surfaces of the core material 4 and are introduced to an IR heater 9 by which the cladding metals are heated to 250 to 500 deg.C; thereafter, these materials are rolled by a rolling mill 13 to form the three-layered clad 18. The clad is taken up on a take-up reel 20. Thermocouples 21, 22 detect the temp. and a controller 12 controls an IR lamp 10 to maintain the specified temp. The core material 4 is a material having a low m. p. and exists between the cladding metals 5 and 6, by which the core material is heat insulated and is prevented from heating up too much. The three-layered clad is easily produced.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention manufactures by rolling a three-layer cladding material in which a soft or low melting point core material is laminated with harder or higher melting point cladding materials on the front and back surfaces of the soft or low melting point core material. It is about the method.

(Prior Art) In recent years, clad metal plates in which different types of metal plates or metal foils are laminated have been used in fields such as building materials, automobiles, and home appliances, as well as in materials such as electrode materials and bimetals.

This type of clad metal plate is made by selecting metals with different properties and imparting the desired properties.However, metals with different properties are made in such a way that they do not deteriorate in their properties and do not peel off in practice. Difficulties are involved in joining.

Clad plates made of dissimilar metals are manufactured using various methods, such as adhesive methods and explosion bonding methods.
There are limits to the selection of adhesives and bonding strength, and the explosion bonding method has limits to the objects that can be used, so it is limited to special products.

Therefore, a rolling method is generally used.

Problems when manufacturing clad metal plates by rolling include non-uniform deformation due to differences in deformation resistance, and a decrease in bonding strength due to the formation of an oxide film depending on the metal used. To this end, various improvements have been made to the rolling conditions.

For example, Japanese Patent Publication No. 47-48096 discloses a method of cladding a stainless steel strip and an aluminum strip, in which the oxide film of both metals is removed with an abrasive, and then the cladding method is performed in a heating furnace in a non-oxidizing atmosphere or in a vacuum. Introduced stainless steel is 371~
At 1010°C, the aluminum is heated from a lower temperature of 240°C to below its melting point to soften it, and after being laminated in a furnace,
It describes a method of rolling at less than 60%.

However, although this method improves the malleability of the stainless steel strip heated to a high temperature, the bonding surface with aluminum may reach a temperature higher than the melting point of aluminum, and Fe is added to this interface.
A problem arises in that intermetallic compounds such as kt and q are formed, making it difficult to press.

Furthermore, in Japanese Patent Publication No. 54-9985, stainless steel plates and aluminum plates are heated in a heating furnace in a non-oxidizing atmosphere for 200 minutes.
℃ or above and below the recrystallization temperature of aluminum, suppressing the degree of softening of the stainless steel provided in the prior patent publication due to high temperature heating, and crimping by rolling to produce a laminated plate with excellent adhesion. A method is disclosed. That is, the deformation resistance of the stainless steel plate is made greater than that of the aluminum plate, causing slight plastic deformation, but depending on the rolling reduction rate (less than 40%),
Deformation such as rolling warpage may occur due to the difference in deformation resistance between the two plates.

In each of the above-mentioned prior art, heating prior to clad rolling is performed in a heating furnace, and heating in a gas furnace or electric furnace requires large-scale equipment with insulation materials, etc., and has a large thermal inertia. Therefore, the response of temperature control is slow. In addition, preheating is required before the heating device enters a steady state before operation.

On the other hand, when manufacturing a composite material of aluminum foil and steel plate, the coated surface of the aluminum foil coated with adhesive is heated, and the steel plate heated in a preheating furnace is overlapped and bonded by pressing with a heat roll. , a method for making composite materials was published in 1983
It is disclosed in Japanese Patent No.-223683. According to this disclosure, it is noted that an infrared heater is used as a heat source to preheat the aluminum foil to press and bond the aluminum foil and steel plate together using an adhesive, but the essence of the invention is that the The purpose is to prevent wrinkles from forming on the foil.

(Problems to be Solved by the Invention) When dissimilar metals are clad rolled, various problems arise in the rolling process due to differences in deformation resistance, as also exists in the above-mentioned prior art.

The present invention aims to improve these problems, and includes:
The laminate is heated using an extremely compact infrared heating furnace with good thermal control, and the cladding material, which has a higher deformation resistance than the core material, is crimped onto the core material and both sides of the core material. , an object of the present invention is to provide a method for manufacturing by rolling.

(Means for Solving the Problems) In order to achieve the above object, the gist of the present invention is that when rolling and manufacturing a three-layer clad material in which a core material and laminate materials are bonded to the upper and lower surfaces of the core material, Using a material with lower deformation resistance or lower melting point than the laminate material, each laminate is heated rapidly with infrared rays from the surface of each laminate in close proximity to the upper and lower surfaces of the core material, and then passed through a rolling roll. The present invention is a three-layer clad rolling method characterized by crimping.

Furthermore, the present invention is suitable for producing a relatively thin cladding material (foil) such as an electrode material for an electrolytic capacitor, and therefore it is preferable to use the rapidly solidified tube as a cladding material.

Aluminum and aluminum alloys are generally often used for the above electrode materials, but when these metals are used as cladding materials, the heating of the clad material before rolling is 250 to 500°C.
A range of is preferred.

The present invention will be explained in detail below.

FIG. 1 is an example (schematic diagram) of an apparatus for carrying out the present invention. In the figure, 1 is a core material unwinding reel, 2 and 3 are laminated material unwinding reels, each of which is unwound from one reel. The core material 4 and the laminate material 5.6 are arranged with the core material 4 in the center, and the laminate material 5.6 is placed near the front and back surfaces of the core material 4 on the entry side guide roll 7.
．． 8, and each of these villages is successively introduced into the infrared heating device 9 while maintaining an appropriate interval.

The infrared heating device 9 has infrared lamps 10 at the top and bottom in the width direction,
A reflecting plate 11 is provided, and each surface of the bonding materials 5 and 6 is heated through the core material 4 and the upper and lower bonding materials 5,6. Reference numeral 12 denotes a control device, which is connected to, for example, thermocouples 21 and 22 that measure the temperature of the laminate 5.6 on the outlet side of the device 9 and the ambient temperature inside the device 9, and controls the output of the infrared lamp 10.

Reference numeral 13 denotes a rolling mill, which in this example is comprised of four rolls: upper and lower work rolls 14.15 and upper and lower backup rolls 16.17 that support these.

That is, the core material 4 and the heated laminate material 5.6 that have come out of the heating device 9 are bitten by the upper and lower work rolls 14.15, and are compressed and bonded to form the cladding material 18. This clad material 18 is guided to a guide roll 19 and wound onto a take-up reel 20.

(Function) The present invention produces a cladding material using the above-mentioned apparatus, and although the type of cladding material to be targeted is not particularly limited, it is more suitable for producing thin materials. For example, aluminum foil, aluminum alloy foil, iron plate gold leaf, etc. manufactured by the rapid solidification method, stainless steel manufactured by rolling, etc.
There are thin plates (including foils) made of titanium, copper, or alloys thereof.

When manufacturing cladding materials using such materials,
Figure 1: When starting up the device, take up the take-up reel 20 in advance.
Unwind the dummy coil that was previously wound on the dummy coil, and feed it backwards so that its tip comes from between the upper and lower work rolls 14 and 15 through the infrared heating device to near the entrance guide roll.
Core material 4 and plying board 5 transported from unwinding reel 1.2.3
．． Weld and connect 6 to the tip of the dummy coil. Thereafter, the roll gap is set, and the take-up reel 20 is operated simultaneously with the rotation of the work roll to start winding and infrared heating by the heating device 9.

In this way, the core material 4 and the laminate material 5.6 are supplied from each unwinding reel 1.2 and 3 with a set tension, and are heated by the heating device while being pulled by the dummy coil.
After being rolled by the rolling mill 13, it is continuously wound onto a take-up reel.

The heating device 9 reaches a desired temperature immediately when the infrared lamp 10 is turned on. The heating temperature varies depending on the type of material, but for example, if the core material is made of an aluminum alloy, the aluminum alloy should be heated at a temperature that improves the malleability but does not cause deterioration of the material. For example, for quenched foil, a rough guideline is 5.
The temperature is preferably 00°C or lower. However, the deformation resistance of the aluminum alloy cannot be reduced at too low a temperature, and the temperature should be 250°C or higher. In this heating device, the surfaces of the laminated materials 5 and 6 are heated, but the core material 4 between the laminated materials 5 and 6 is thermally insulated and does not rise in temperature that much. In the present invention, since the core material 4 is selected from a material with low deformation resistance, there is no need to raise the temperature, and if the temperature rises to a high temperature, a shielding plate is installed between each of the laminates and the core material. (not shown) is preferably provided to prevent temperature rise.

The heating temperature is set using the outlet thermocouple 21 and the internal thermocouple 2.
2, the temperature of the surface of the laminated plate 5.6 and the atmosphere inside the device is measured, and the temperature is fed back to the control device 12, and the output of the control device 12 is controlled to a predetermined value.

This temperature measurement is not limited to the thermocouple method, and it goes without saying that other methods, ie, known non-contact temperature measurement devices, may be used.

The roll gap of the rolling mill is adjusted to obtain the desired thickness of the cladding material based on the thickness of the core material and the cladding material, but each material must be tightly crimped to form a three-layer cladding. First, for this purpose, it is necessary to set the rolling reduction rate to be at least 5%. Furthermore, if the rolling reduction rate is too high, the degree of work hardening will increase, so the roll gap should be controlled to be 40% or less.

In this way, in the present invention, the core material and the laminate material with higher deformation resistance are arranged side by side, and before rolling and crimping, the laminate material is heated to improve its malleability, and it is also compact. Since it uses infrared heating with good thermal response, it can be heated to a predetermined temperature without being affected by external disturbances, so coil cladding, especially thin materials, can be manufactured efficiently.

(Example) Example 1 Pure i (A) 99.99%) foil with a thickness of 200 am and Att-10% with a thickness of 130 μm manufactured by rapid solidification method.
Zr alloy foil was used. A three-layer clad foil was manufactured using the equipment shown in FIG. 1 using pure AIl foil as a core material and A1 alloy foil as a laminate material in actual operation immediately after set-up, with almost no advance preparation such as preheating required.

Each foil was paid out from each reel, and the cladding material AA' alloy foil strips were placed close to the top and bottom of the core material All alloy foil strip, and the furnace length (
Heating Zone) The sample was introduced into a 600 mm infrared heating device, heated, and then rolled. In a heating device, the upper and lower alloy foil strips were heated to 350° C. using an infrared lamp. At this time, the AI foil strip temperature was 200°C. Since the temperature of the AI foil strip is rising, a heat shielding plate with an internal water-cooled tube made of iron plate is inserted between the alloy foil strip 1 for the number plate and the foil strip for the core material 1. Material A [By preventing heat from flowing into the foil, it was possible to raise the temperature of the AI foil strip to 100°C.

The core-joint material heated in this manner and having a temperature difference was rolled with a rolling reduction ratio of 20% to produce a three-layer cladding material having a thickness of 370 am and having a dense structure.

A bending test and sequential observation were performed to test the adhesion of the cladding foil. The bending radius of the punch in the bending test is 1011
Two types of rectangular test pieces, 11 mm and 2.5 mm, were bent to 90°. The cladding material cracked on the outer layer of rapidly cooled foil, but the pure aluminum core material stopped the cracking. This crack did not propagate across the boundary between the core material and the quenched foil. This shows that the bonding strength is at least stronger than the bending strength of the quenched foil.

Furthermore, when observing the surface perpendicular to the bonding process, it was found that the pure aluminum deformed as the thickness of the quenched foil changed, closely following the irregularities. Therefore, it can be seen that there is no gap between the laminated material and the core material, and that they are in very good contact.

Further, the cladding material was etched to enlarge its surface area and then subjected to a chemical conversion treatment to form an oxide film on the enlarged surface, thereby forming an electrode material for an electrolytic capacitor.

When processing the electrode, the core material heated to 200℃ (without shielding plate) is a little harder and more difficult to process than the clad material whose core material is heated by infrared radiation to 100℃, but as a whole, electrodes with extremely excellent characteristics can be obtained without any problems. Ta.

Example 2 A three-layer cladding was produced using the equipment shown in Figure 1 in the same manner as in Example 1, using a rolled stainless steel strip with a thickness of 300 + ua as a cladding material and a pure AI strip with a thickness of 400 um as a core material. . The running speed of each strip is 2.5 m.
/win, the heating temperature of the laminated material by infrared heating is 50
The temperature was 0°C.

The thus heated material was rolled at a reduction rate of 40% to produce a cladding material.

A bend-back test and an EPMA analysis were conducted to test the adhesion of the aluminum/stainless steel clad. The bending/unbending test is a test in which a cladding material cut into a rectangular shape is bent to 90° using a punch with a radius of 5 mm, and then bent back until it becomes almost flat.

Almost no cracking or peeling occurred in any of the claddings. This shows that they are bonded with considerable strength. Further, EPMA analysis shows that there are no inclusions such as oxides at the bonding interface, and the bonding is strong.

As described above, according to the present invention, a corrosion-resistant clad steel with excellent adhesion and workability can be obtained extremely easily.

Note that various cladding materials such as AA! can be used in the method of the present invention. ,
Combinations selected from stainless steel, Cu, Tj, Fe, and alloys thereof are possible, and clad steel having the characteristics of each metal can be obtained.

(Effects of the Invention) As explained above, according to the present invention, dissimilar metals having different deformation resistances can be rolled,
It can be crimped, and three-layer cladding can be easily produced depending on the purpose.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an example of equipment for implementing the present invention. Core material rewinding reel 3, laminating material rewinding reel 4. Core material 6, laminating material
7.8. Entry side guide roll infrared heating device 10. Infrared lamp reflector 12. Control device rolling mill 14. Upper work roll Lower work roll Upper backup roll Lower backup roll Cladding foil 19. Guide roll take-up reel 21, thermocouple in outlet thermocouple device

Claims (3)

[Claims] (1) When manufacturing a three-layer clad material by rolling a core material and cladding materials bonded to its upper and lower surfaces, a material with lower deformation resistance or a material with a lower melting point than the cladding material is used as the core material, and each cladding material is A three-layer cladding rolling method characterized by rapidly heating infrared rays from the surface of each laminate in close proximity to the upper and lower surfaces of the core material, and then passing it through rolling rolls and crimping it. (2) The clad rolling method according to claim 1, wherein at least the laminate is an alloy foil manufactured by a rapid solidification method. (3) The clad rolling method according to claim 1 or 2, wherein the laminated material is heated by infrared rays to 250 to 500°C.