JPH06226307A - Method for processing joined part of aluminum rolled coil - Google Patents

Abstract

PURPOSE:To manufacture a high-quality large-sized coil uniform in apperance characteristics of the whole of coil at low cost without increasing the scale of casting/hot rolling equipment on the upstream side of the connecting stage because the appearance characteristics of the joined part and base materials, especially, the surface properties of an oxide film or the like are equaled at the time of joining small-sized aluminum rolled coils to each other by butt pressure welding. CONSTITUTION:After the aluminum rolled coils 1, 1 are welded by pressure to each other by butt pressure welding, the surface of the joined part 3 is faced to the same degree as the thickness of the base material, the faced part is ground with the powder of oxide or an oxidized film of 50-1000Angstrom thick is provided by applying oxidation treatment to the faced part and, after that, further the whole of coil is rolled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating an aluminum rolled coil joint having excellent appearance quality of the joint, and particularly to make the surface properties of an oxide film and the like of the joint and the base metal equal to each other. The present invention relates to a processing method for suppressing uneven appearance quality.

[0002]

2. Description of the Related Art In recent years, there has been a strong demand for higher efficiency in the industrial world.
There is a demand for increasing the size of the coil in the tertiary processing of various products using the metal coil to reduce the number of handlings during the coil processing and improve the efficiency. Usually, in order to increase the size of such a coil, it is necessary to increase the size of everything from the casting equipment, which is the beginning of the coil manufacturing process, to the final finishing equipment. Therefore, it is quite necessary to meet the demand for such enlargement. Equipment investment was required.

In order to deal with such a problem, by joining two coils during the coil manufacturing, for example, at the time of cold rolling to manufacture a large coil having a length twice that of the coil, cold rolling equipment can be used to cope with the large equipment. A method has been proposed in which only the finishing equipment is used, and the casting equipment and hot rolling equipment before that are kept as they are.

[0004]

However, it is a matter of course that the method of joining the coils requires that the joint be sound and that the mechanical processing characteristics thereof are equivalent to those of the base metal, depending on the application. The uniformity of other characteristics is also required, and in the case of a coil for can material, for example, the appearance characteristics of the joint are required to be equivalent to those of the base material.

In such a case, by adopting a solid-state pressure welding method such as flash butt welding or upset butt welding as shown in FIG. 1 as the joining method, the structure of the joined portion can be made to the same level as the base metal. . However, even with these methods, non-uniformity in shape due to plastic deformation due to solid-phase pressure contact occurs as shown in FIG.
In order to eliminate this, it is necessary to chamfer the joint portion as shown in FIG. 1 (c). However, this chamfered part has a difference in appearance characteristics due to the difference from the base metal part of the surface oxide film, and even if cold rolling is further performed after chamfering, the difference in appearance characteristics in the final product such as a can. There is a problem that it remains as it is and cannot be used.

[0006] As another method, a method of selectively removing the joint portion during the production of the tertiary processing has been studied, but since the difference in the appearance color tone of the joint portion is subtle, the manufacturing such as rolling and winding after the joint is performed. It is difficult to identify on the line and it is difficult to sort and mix into the final product. On the other hand, at the stage of the final product, it is required that the appearance is exactly the same as the base material, so even a slight difference in appearance characteristics poses a problem. Probability is high.

As described above, according to the conventional method, the appearance characteristics of the joint portion when the butt pressure welding is performed are different from those of the base material.
There is a problem that when the joint is mixed in the final product, it becomes a defective product. The present invention has the main object to eliminate defects in the joint portion when the small coil is joined into a large coil by making the joint portion and the base material have the same appearance characteristics, particularly surface properties such as an oxide film. Therefore, it is an object of the present invention to manufacture a high-quality large-sized coil at low cost without modifying the equipment of the upstream process.

[0008]

Means for Solving the Problems As a result of various investigations for solving the above-mentioned problems, the inventors have made the surface properties of the oxide film and the like of the joint and the base metal equal by treating the vicinity of the joint. As a result, they have found that they can achieve the present invention. That is, the present invention, as described in claim 1, in butt pressure welding of aluminum rolled coils, after the pressure welding, the joint portion is chamfered to the same extent as the plate thickness of the base material, and the chamfered portion is polished with oxide powder, After that, the whole coil is further rolled, which is a method for treating an aluminum rolled coil joint having excellent appearance quality of the joint. Further, as described in claim 2, in the butt welding of the aluminum rolled coils, after the welding. The joint portion is chamfered to the same thickness as the base material, and the chamfered portion is subjected to an oxidation treatment to have a thickness of 50-
This is a method of treating an aluminum rolled coil joint having excellent appearance quality of the joint, which comprises rolling an entire coil after providing an oxide film of 1000 angstrom.

Here, the material and plate thickness of the aluminum rolled coil are not particularly limited, but normally, JIS A110.
0,3003,3004,5052,5182,606
1 etc. can be preferably applied. The plate thickness at that time is not particularly limited, but is preferably 1 to 10 mm. The method of butt pressure welding is not particularly limited, but solid-state pressure welding methods such as flash butt welding, upset butt welding, and high frequency pressure welding can be preferably applied. The joint portion whose plate thickness is increased by the plastic deformation in the butt pressure welding is chamfered to the same degree as the plate thickness of the base material, but the chamfering method is preferably mechanical cutting.

As the oxide in the treatment according to the first aspect, powder of oxide of aluminum, magnesium or the like is preferable, and the size of the powder is preferably 0.1 to 10 μm. The polishing method may be a dry method or a wet method using a suspension of oxide powder.

The method of the oxidation treatment according to claim 2 is not particularly limited, but heating, steam spraying, immersion in boiling water or the like is preferable, and the thickness of the oxide film is 50 to 1000 angstroms.

Although the rolling reduction of the rolling performed after the pressing / face-cutting is not particularly limited, it is usually 50 to 90%, and the plate thickness at that time is preferably 1 to 5 mm.

[0013]

The reason why the appearance quality of the joint is as good as that of the base material by the method of the present invention is considered as follows. That is, in the pressure welding of the aluminum rolled coil as shown in FIG. 1A, the pressure welding causes a plastic deformation in the joint portion as shown in FIG. For this reason, as shown in FIG. 1C, this raised portion is removed by chamfering or the like to flatten the plate thickness. However, because the surface oxide film is removed by the chamfering, the surface properties such as the oxide film thickness and the surface roughness of the joint are different from those of the base metal, and the chamfered part and the base metal are different. The difference in surface texture cannot be eliminated by subsequent ordinary rolling or the like and is carried over to the final product, causing problems such as product defects. On the other hand, in the first aspect of the present invention, after the chamfering of the joint, only the chamfered surface is polished with the oxide powder of aluminum, magnesium, etc. By biting and then rolling, these oxide powders are dispersed appropriately, and as a result, the surface texture of the joint can be made similar to the surface texture of the base material. Here, if the size of the oxide powder is less than 0.1 μm, the cost of the oxide powder becomes high and its effect is saturated. On the other hand, 10μ
If the size exceeds m, the roughness becomes large, which is not preferable.
Therefore, the size of 0.1 to 10 μm is desirable.

Further, in the second aspect of the present invention, after chamfering the joint portion, only the chamfered surface is subjected to oxidation treatment so that the surface texture of the joint portion is close to the surface texture of the base material, and thereafter the entire coil is rolled to bond. The difference in surface texture between the base and the base material can be leveled. The thickness of the oxide film is 50 to 1000 angstrom. If the thickness of the oxide film is less than 50 angstrom, the effect of the oxidation treatment is not sufficient, and the difference in appearance between the base material having the oxide film and the chamfered portion from which the oxide film has been removed by chamfering remains. On the other hand, if the thickness exceeds 1000 angstroms, the oxide film in the chamfered portion becomes too thicker than the base material, resulting in a difference in appearance characteristics. Therefore, the thickness of the oxide film is 50 to 1000 angstroms.

As described above, by making the state of the oxide film of the joint close to that of the base material and rolling, the difference in the appearance characteristics between the parts in one final product can be visually confirmed. Can be reduced to an almost unnoticeable level.

[0016]

EXAMPLES Examples of the present invention will be described below. [Example 1] Hot thickness 5 mm and width 1000 mm
The JIS A3004 aluminum alloy coil of No. 1 was pressure welded by flash butt welding under the following conditions. Upset pressure: 80 tons Upset current: 750 KA Flash time: 3 cycles After that, the joint was machined until the plate thickness was about the same as the base metal plate thickness. Further, a water suspension containing alumina particles having a size of 3 μm was applied to the chamfered portion and polished with a cloth. Then, rolling and intermediate annealing were performed to give a final plate thickness of 0.3 mm. A test piece is prepared from the part including the joint part of the coil, drawn and DI processed to form a body of a two-piece can, and the difference in appearance between the joint part and the base metal part in the vicinity of the joint part is visually observed. No particular difference in appearance was observed when examined by. For comparison, the appearance characteristics of the can body obtained under the same conditions as above except that the chamfered portion was not polished were evaluated, and a remarkable difference in appearance was observed.

Example 2 A JIS A3004 aluminum alloy coil having a hot thickness of 5 mm and a width of 1000 mm was flash butt welded under the following conditions. Upset pressure: 80 tons Upset current: 750 KA Flash time: 3 cycles After that, the joint was machined until the plate thickness was about the same as the base metal plate thickness. Further, after sealing the periphery except for the chamfered portion with a resin tape, the periphery of the joint portion was immersed in boiling water at 100 ° C. for 30 seconds for oxidation treatment. Then, rolling and intermediate annealing were performed to give a final plate thickness of 0.3 mm. A test piece is prepared from a portion including the joint portion of the coil, drawn and DI processed to form a body of a two-piece can, and the difference in appearance between the joint portion and the base metal portion in the vicinity of the joint portion is visually observed. When examined, no particular difference in appearance was observed. For comparison, the appearance characteristics of the can body obtained under the same conditions as above except that the chamfered portion was not subjected to oxidation treatment were evaluated, and a remarkable difference in appearance was observed.

[0018]

[Effect] As described in detail above, according to the method of the present invention, even when small coils are butted and joined together by pressure welding, the appearance characteristics of the joint portion and the base material, especially the surface properties of the oxide film and the like are equal. Therefore, the entire coil after joining can be treated as a large coil having uniform appearance characteristics. Therefore, according to the present invention, even in the production of an aluminum rolled coil used for applications such as a can material that is required to have an appearance quality and is produced in a large amount and at high speed by continuous processing, the present invention relates to the present invention after cold rolling. By applying the method for treating the joint portion of the rolled metal coil, it becomes possible to manufacture a high-quality large-sized coil at low cost without increasing the size of casting and hot rolling equipment in the upstream process from the connecting process.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing butt pressure welding of rolled metal coils, where (a) is a state before pressure welding, (b) is a state immediately after pressure welding, and (c) is a state after chamfering a deformed portion by pressure welding. Is shown.

[Explanation of symbols]

 1, 1 '... Rolled metal coil 2, 2' ... Clamp 3 ... Joined part

Claims (2)

[Claims] 1. In butt pressure welding of rolled aluminum coils, after the pressure welding, the joint portion is chamfered to the same thickness as the base metal, the chamfered portion is polished with oxide powder, and then the entire coil is further rolled. A method for treating a rolled aluminum coil joint having excellent appearance quality of the joint. 2. In the butt pressure welding of rolled aluminum coils to each other, after the pressure welding, the joint portion is chamfered to the same thickness as the base metal, and the chamfered portion is subjected to an oxidation treatment to have a thickness of 50 to 1
A method of treating an aluminum rolled coil joint having excellent appearance quality of the joint, which comprises rolling an entire coil after providing an oxide film of 000 angstrom.