JPH05148664A - Aluminum alloy sheet for forming excellent in galling property - Google Patents

Abstract

PURPOSE:To reduce the generation of the breaking of a material such as the cutting of a can caused by galling in the process of working by providing the surface with a specified amt. of phosphate film. CONSTITUTION:The surface of an aluminum alloy sheet for forming is provided with a phosphate film of 0.1 to 20g/m<2>. This is furthermore coated with animal and vegetable series lubricating oil or mineral series lubricating oil or synthetic lubricating oil or their mixed lubricating oil. As the aluminum alloy, e.g. 3004 alloy used for DI can barrels and 5052 and 5182 alloy utilized for can cover materials are used. In this way, the wear of a tool such as a die caused by coagulated materials is reduced, and the service life of the tool can be prolonged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aluminum alloy plate which is less likely to cause galling during ironing, and more particularly to an aluminum alloy plate suitable as a can body.

[0002]

2. Description of the Related Art In the present invention, an aluminum alloy plate means an industrial pure aluminum plate and various aluminum alloy plates. Generally, drawing and ironing (Ironin)
In the case of forming with g), defects or discoloration, that is, galling, may occur on the surface of the material plate during ironing substantially parallel to the ironing direction. This galling significantly deteriorates the quality of the surface of the raw material plate, and especially in applications where the aluminum base is exposed instead of coating the entire can body, such as in aluminum cans, this galling does not occur. It is a fatal surface defect that significantly impairs the appearance of the product. Further, if the goring is severe, material breakage occurs during ironing, interrupting the work and reducing the work rate, and debris sometimes damages the ironing tool and the processing equipment.
Further, the occurrence of goring causes wear of a tool such as a die and shortens the life of the tool. Due to the above problems, it is strongly desired to suppress the occurrence of goring in the ironing process.

The mechanism of the occurrence of galling in an aluminum alloy plate is that the ironing die is brought into direct contact with the surface of the aluminum alloy plate due to poor lubrication during ironing, and aluminum alloy pieces and hard particles such as Al ₂ O ₃ are contained in the alloy. It is considered that it is caused by peeling from the plate surface and adhering to the ironing die, and the agglomerate rubs the surface of the aluminum alloy plate. Therefore, various methods have been devised to prevent the occurrence of galling by improving the lubrication conventionally. As for the lubricating oil to be applied, 1) Re-oil treatment is performed as a pre-ironing treatment, and the lubricating oil stock solution is aluminum. Apply to alloy plate to improve lubricity 2) Combine various composition ratios of lubricating oil during ironing, and use appropriate composition ratio of lubricating oil that will not run out of oil 3) Adjust surface roughness of material plate There is a method of improving oil retention by unevenness of the plate surface. In addition, the occurrence of galling is also suppressed by controlling the material properties such as the structure of the aluminum alloy plate. For example, AA3004 alloy is currently widely used for can body materials. One of the reasons is that it has relatively high strength and excellent formability, and its mechanical properties such as work hardening during ironing is relatively small. Although it is excellent, a large amount of Al—Mn—Fe-based coarse crystallization compound is present, and this coarse crystallization compound exhibits solid lubricity, and due to the voids formed in the vicinity of the crystallization compound, the oil retaining property is improved. It is also one of the reasons why this alloy is adopted as a practical alloy because it is less likely to cause galling due to the effects such as improvement of the effect and the effect of self-cleaning of the ironing die.

[0004]

In recent years, various researches and developments have been made on combinations of alloy component compositions, manufacturing methods, etc. of aluminum alloys for can body materials in response to demands for thinning and high strength of can body materials. .. For example, there have been devised methods such as uni-alloying, in which a can lid material and a can body material are made of the same alloy, which have been conventionally made of different alloy materials, and a manufacturing method using a ingot having a fine structure by rapid solidification casting. However, for example, 5052, 5082, 51 which have been widely used for can lid materials in the past.
Although the developed alloy based on the alloy such as 82 is superior to the 3004 alloy in terms of strength and formability, it has a large deformation resistance to ironing and has a poor solid lubrication effect on the material, making ironing difficult and causing galling. Cheap. Further, even in the conventionally used 3004 alloy, in the manufacturing method in which the cooling rate at the time of casting is higher than that in the generally used DC casting method such as continuous casting and rolling, the crystallized compound diameter becomes small and the alloy components such as Mn Since the amount of solid solution increases, the strength is improved, but work hardening is large, and like the 5000 series alloy, ironing is difficult and galling is likely to occur. Although various materials having excellent strength have been developed as described above, the occurrence of galling in the ironing process is unavoidable, which hinders its practical use in applications such as can body materials for DI processing. ..
In view of the above problems, the present invention suppresses the occurrence of galling in the current aluminum alloy sheet and the aluminum alloy sheet such as the high-strength material to improve the ironing workability, and DI processing suitable for high-strength thinning The purpose of the invention is to supply can bodies and extend the die screening interval during DI processing to improve the work rate and extend the life of tools such as dies.

[0005]

In order to solve the above problems, the inventor of the present invention has variously studied the ironing method, the forming surface of the processing tool, the aluminum alloy composition, the material surface such as the manufacturing conditions, and the like. Focusing on the fact that the means for providing a lubricious coating on the substrate is versatile regardless of the alloy composition and manufacturing conditions of the aluminum alloy sheet as a raw material, various surface treatment methods have been studied, and as a result, the present invention has been achieved. That is, the invention of claim 1 of the present application is an aluminum alloy plate for molding having excellent galling properties, which is characterized in that a phosphate coating of 0.1 to 20 g / m ² is provided on the surface thereof. The invention provides a surface with a phosphate coating of 0.1 to 20 g / m ² ,
Further, it is an aluminum alloy plate for molding which is excellent in galling characteristics and is characterized by being coated with an animal or plant-based or mineral-based lubricating oil. The aluminum alloy plate used as the base material can be used without any problems in addition to the one produced by the semi-continuous casting method which has been widely used in the past, and the one produced by using the ingot by the casting method with a high cooling rate such as continuous casting and rolling. be able to. As the phosphate, zinc phosphate, iron phosphate, manganese phosphate,
Although there are chromium phosphates and the like, chromium phosphates and zinc phosphates are preferable in terms of adhesion and the like. Examples of the method for forming the phosphate coating include a dipping method using a chemical conversion treatment solution containing a phosphate and an electrolytic treatment method. In addition, in order to improve the adhesion of the phosphate coating, a base treatment such as a chromium chemical conversion treatment may be performed. As the lubricating oil, it is preferable to use a mineral lubricating oil or a synthetic lubricating oil for normal ironing, but the component composition is not particularly limited, and an animal lubricating oil, a vegetable lubricating oil or the above mixed lubricating oil is used. Can be used. Further, as a method for applying the lubricating oil, an ordinary oil application method such as an electrostatic application method or a roll coating method can be used. When lubricating oil is applied, the properties of the phosphate coating change over time in the atmosphere, so it is desirable to apply the coating immediately after applying the phosphate coating. Manufacture a plate and apply it just before ironing,
Alternatively, it may be applied by a method of coating just before or during the pre-process (drawing process) of the ironing process. The aluminum alloy plate is a 3000 series alloy such as 3004 which has been conventionally used as a can body material as described above, and a 5000 series alloy such as 5052, 5082, 5182 which is mainly used as a can lid material and their improved alloys. Can be preferably applied, but is not particularly limited thereto. However, it goes without saying that when it is used as a beverage can or a food can, the alloy component composition satisfies the standards such as the Food Sanitation Law.

[0006]

As described above, the mechanism of the occurrence of galling in the aluminum alloy plate is 1) due to poor lubrication during the ironing process, etc. 1) The surface of the aluminum alloy plate comes into direct contact with the ironing die and the aluminum alloy pieces adhere to the die. 2) Oxides such as Al ₂ O ₃ and hard particles such as fine intermetallic compounds such as Al (Mn, Fe) Si generated on the surface of the aluminum alloy plate are separated from the surface of the plate and adhere to the ironing die. It is considered that the cohesive lumps thus formed are caused by rubbing the surface of the aluminum alloy plate. On the other hand, in the aluminum alloy plate according to the present invention, 1) the phosphate coating provided on the plate surface exhibits high oil retention, and lubrication failure such as oil shortage of lubricating oil does not occur 2) lubrication failure Even if it occurs, the phosphate coating covers the surface of the aluminum alloy plate, preventing direct contact between the aluminum alloy surface and the ironing die. 3) Preventing aluminum oxidation by coating the surface of the aluminum alloy plate. , Which causes goling A
Suppressing the formation of hard oxides such as l ₂ O ₃ 4) By coating the surface of the aluminum alloy plate, A
By preventing hard particles such as oxides such as l ₂ O ₃ and fine intermetallic compounds such as Al (Mn, Fe) Si from peeling from the plate surface, adhesion by ironing die does not occur. The occurrence of goring can be suppressed. Although there are various methods for coating the surface of the aluminum alloy plate other than the phosphate coating, the phosphate coating has better compatibility with aluminum than other coatings and is less likely to peel off. Further, since the phosphate coating itself is softer than the aluminum alloy material, even if the coating itself peels off and wears into fine particles and adheres to the ironing die, it is a coagulated lump that is softer than the aluminum alloy plate, so that no galling occurs.

[0007]

EXAMPLES Examples of the present invention will be described below. The aluminum alloys used as test materials were the 3004 alloy currently used for DI can body materials and the 5052 and 5182 alloys used for can lid materials. The alloy composition is shown in Table 1.

[0008]

[Table 1]

An aluminum alloy is cast by using each alloy shown in Table 1 according to each manufacturing condition shown in Table 2, and the ingot is rolled by hot rolling or cold rolling to a predetermined thickness, and an aluminum alloy plate is obtained. Then, intermediate annealing was performed and final cold rolling was performed to a thickness of 0.3 mm. The 3004 alloys (Nos. 1 to 4) were subjected to final annealing at 105 ° C in order to improve the deep drawing and redrawability. The aluminum alloy plate obtained under each production condition is degreased, washed with water, and surface-adjusted, then immersed in a zinc phosphate solution at 43 ° C (PB-L3020 manufactured by Nippon Paint Co., Ltd.) for 2 minutes, then washed with water, dried and cupped. Each of the invention examples was prepared by applying a lubricating oil for use as a stock solution. The amount of zinc phosphate coating film formed is shown in Table 2. A conventional example was the same aluminum alloy plate as in the invention example, which was coated with the cupping lubricant as it was without a phosphate coating.

[0010]

[Table 2]

Explaining each sample number shown in Table 2, No. 1 and No. 2 are the conventional material 3004 alloy DC casting under the condition of the cooling rate of about 10 ° C./s by the conventional method. It is manufactured by obtaining lumps. The intermediate annealing is performed in a continuous annealing furnace (CAL) at a heating rate of about 20 ° C /
s, cooling was performed immediately after reaching the temperature, and the cooling rate was about 20 ° C./s.・ For Nos. 3 and 4, changing the casting conditions to N
This is an ingot having a plate thickness of 7 mm produced by continuous cast rolling (Strip cast) with a high cooling rate using the same alloy as o1 and o2. The cooling rate at the center of the ingot was about 100 ° C./s. Nos. 5 and 6 are alloys of Nos. 1 and 2 which are different from those of Nos. 1 and 2 and used the conventional 5052 alloy as a can lid material.・ No. 7 and 8 are 518 that are conventionally used as can lid materials by changing the alloy system to No. 1 and 2.
Batch furnace (BAF) with intermediate annealing using 2 alloys
The heating rate is about 35 ° C./h, the ultimate temperature is 320 ° C., the holding time is 2 hours, and the cooling rate is about 35 ° C./h. Each odd number is a conventional example or a comparative example in which oil is applied to an aluminum alloy plate as it is, and each even number is an example of the present invention by applying a zinc phosphate coating treatment.

For each sample, DI processing was performed after cupping and the goring property was evaluated. For the evaluation of the goring property, the D of 3004 alloy currently used as a can body material is used.
The level of the conventional example (No. 1) made of C casting material is set to ◯,
Goling occurs, but DI molding can be done in about several tens of cans △, can be broken out by several cans due to galling x, conversely, no galling occurred and surface DI was excellent and DI molding was very good The item was marked as ◎. The results are shown in Table 3.

[0013]

[Table 3]

As shown in Table 3 above, under all conditions, the galling property is improved in the inventive examples provided with the zinc phosphate coating as compared with the conventional examples and the comparative examples. In No. 1 and No. 3 conventional DC casting materials of 3004 alloy, the occurrence of galling is small even without the zinc phosphate coating, but in the invention examples, the galling property is further improved. Therefore, by using the aluminum alloy plate of No. 2 invention example, it is possible to reduce the number of times the ironing die is cleaned during the ironing process, and the tool life is extended. No 3.4 is 3004
The alloy was made into an aluminum alloy plate by continuous cast rolling with a high cooling rate (Strip cast), and it could not be formed by ironing without a zinc phosphate coating treatment, whereas in the invention example No. 1 It has a galling property similar to that of the conventional example by DC casting. Further, even in the case of the No. 5-8 5000 series alloys, the deformation resistance to ironing is large and the solid lubrication effect of the material is poor, so that ironing workability is poor and galling is likely to occur. Or, it shows a better result than the conventional example. That is, except for the conventional example, the result of the galling was severe or the result could not be formed due to the defect.However, any of the zinc phosphate coatings of the present invention example coated with oil had a surface state equal to or higher than that of the conventional example. Goods are obtained, and there is no occurrence of running out of can due to goring.

[0015]

As described above in detail, according to the present invention, it is possible to provide an aluminum alloy plate for forming which is less likely to cause galling during ironing, and therefore, the aluminum base material is exposed such that it is used as a can body. Even in various applications, the appearance of the product is not impaired, and the occurrence of material breakage such as can breaking due to galling during ironing can be minimized. According to the present invention, not only the aluminum alloy plate produced by the DC casting method of 3004 series aluminum alloy, which is a conventional material, but also different alloy series such as 5000 series aluminum alloy, and the structure such as rapidly solidified cast material such as continuously cast rolled material. It is possible to obtain aluminum alloy plates having different galvanic properties, which have good goring properties, for forming. Furthermore, during ironing work, aluminum alloy pieces, oxides such as Al ₂ O ₃ and Al (Mn, Mn,
It is possible to prevent fine intermetallic compounds such as Fe) Si from peeling off from the plate surface, and thus to prevent sticking to the ironing die, extend the die screening interval, reduce the number of cleaning operations, and improve the operation rate. It has the effect of reducing the wear of tools such as dies due to adhered substances and extending the tool life.

Claims (2)

[Claims] 1. An aluminum alloy plate for forming which is excellent in galling property, which is provided with a phosphate coating of 0.1 to 20 g / m ^{2 on} the surface. ^2. A 0.1 to 20 g / m ² phosphate coating is provided on the surface, and animal or vegetable lubricating oil, mineral lubricating oil, synthetic lubricating oil, or mixed lubricating oil thereof is applied. Aluminum alloy plate for forming that has excellent goring properties.