JPS6160143B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing an aluminum alloy plate for deep drawing, which is particularly suitable for caps of whiskey and liquor bottles. Materials such as PP caps (pilfer-proof caps) for whiskey and liquor bottles are required to have the following properties. (1) Excellent deep drawability (less wrinkles); deep drawability includes the drawing process and the drawing conditions after the process (wrinkles, etc.); It is necessary to adjust the mechanical properties, that is, the strength and elongation, and to form a structure in which the formation of ears in the 45° direction with respect to the rolling direction from a crystallographic point of view is slightly predominant. On the other hand, regarding the drawing condition after processing (wrinkles, rough skin, generation of trimming burrs), it is necessary to adjust the orientation of the product material and the crystal grain shape. (2) Low hearing rate. This is required from the viewpoint of improving yield and preventing missing circles. (3) Excellent opening performance. This openability refers to the shearing properties of the perforations machined into the side wall of the cap, and appropriate work hardening and distribution of crystallized substances are required from the viewpoint of strength and crack propagation of the side wall of the cap. Ru. (4) The rigidity of the cap body is high. This is especially
As with PS (press screw) caps, it is necessary to have sufficient strength (idling torque) to prevent the threaded portion from becoming loose, and appropriate work hardening is required. The present invention provides a method for manufacturing an aluminum alloy plate for deep drawing, which can satisfy the above-mentioned required characteristics of caps for whisky, liquor bottles, etc. The method for producing an aluminum alloy plate for deep drawing according to the present invention will be explained in detail. First, the components and component ratios of the aluminum alloy used in the method for manufacturing an aluminum alloy plate for deep drawing according to the present invention will be explained. Cu is an element that imparts strength and work hardening, and if the content is less than 0.02wt%, it will not have this effect.
In addition, if the content exceeds 0.1wt%, the strength will be too high and the work hardening will be too large.
Breakage during molding and unopenability are problems. Then,
Cu content shall be 0.02 to 0.1 wt%. Fe is effective in controlling directionality (synergistic effect with Si) and opening property (proper crystallized product formation), but it does not have this effect when the content is less than 0.3wt%, and when it exceeds 1.0wt%. If it is contained, giant crystallized substances are generated, which adversely affects moldability. Therefore, the Fe content is 0.3~1.0wt
%. Si is effective in controlling directionality (synergistic effect with Fe) and homogenizing the structure (precipitation of Fe and Si), but if the content is less than 0.2wt%, this effect is absent;
If the content exceeds 0.6wt%, moldability will be adversely affected. Therefore, the Si content is set to 0.2 to 0.6 wt%. Note that a more desirable effect can be obtained if Fe/Si<2. Furthermore, if the content of Ti, Zn, and Cr is less than 0.1wt% and the content is appropriate, they will not prevent the effects of the method for producing an aluminum alloy plate for deep drawing according to the present invention. However, as long as the other elements normally contained in aluminum are at the level of impurities, they do not impede the effect. Next, heat treatment in the method for producing an aluminum alloy plate for deep drawing according to the present invention will be explained. After normal soaking, hot rolling, and cold rolling to an aluminum alloy ingot with the above-mentioned ingredients and ingredient ratios, the heating rate and cooling rate are set at 100℃/min or more.
Recrystallization is completed by maintaining the temperature at 380 to 500°C, and then final cold working is performed at a rolling reduction of 30% or higher, with heating and cooling rates set at 100°C/100°C.
The reason why recrystallization is completed by holding the temperature at a temperature of 380 to 500℃ for 10 minutes or more is to make the crystal grains fine and uniform and to increase the amount of solid solution of the contained elements. The surface roughness and shearing properties are excellent, the work hardening properties are improved, and the product sheet has excellent deep drawing properties, excellent opening properties, and rigidity. Therefore, if the heating rate and cooling rate are less than 100°C/min, it will not be effective as it will give room for the growth of crystal grains and the reprecipitation of dissolved elements, and if the temperature is less than 380°C, the recrystallized structure will be uniform. If the temperature exceeds 500℃, the crystal grains will grow and the surface of the drawing cup will become rough.
This leads to a decrease in strength, making it impossible to satisfy the performance as a cap, and furthermore, the retention time is 10%.
Exceeding this amount causes mixed grains due to grain growth and wastes energy. The reason why cold working is performed at a rolling reduction of 30% or more after completion of this recrystallization is to obtain appropriate mechanical properties and a low edge ratio, and this effect cannot be satisfied if the rolling reduction is less than 30%. It is a good idea to perform stabilization annealing as necessary in order to simultaneously obtain appropriate mechanical properties and a low selvage rate after baking the paint. An embodiment of the method for producing an aluminum alloy plate for deep drawing according to the present invention will be described. Example 1 An ingot produced by melting and casting an aluminum alloy with the ingredients and proportions shown in Table 1 by a normal method was hot rolled after soaking at 540°C for 6 hours.
3.0mm (finishing temperature is 300℃). Then, 0.6mm
It was cold rolled to ~0.8 mm, and various recrystallization treatments were performed to make it 0.25 mm. In addition, stabilization annealing was performed to match the mechanical properties. The mechanical properties and cap properties at that time are shown in Table 2, and the degree of work hardening is shown in Table 3 in terms of cap side wall hardness.

【table】

【table】

[Table] As described above, No. 1 (the manufacturing method of an aluminum alloy plate for deep drawing according to the present invention) is superior to those under other manufacturing conditions in terms of deep drawing formability and cap rigidity. I understand. Further, the grain size of No. 1 was 0.22 mm. Example 2 An ingot produced by melting and casting an aluminum alloy having the ingredients and proportions shown in Table 4 by a normal method was subjected to soaking treatment at 540°C for 4 hours, and then hot rolled.
3.0 mm (finishing temperature 300°C). Then 0.6~
It was cold rolled to 0.8 mm, and recrystallization was completed at a temperature of 430° C. with a holding time of 3 minutes at a heating rate of 200° C./min and a cooling rate of 200° C./min. The mechanical properties were then adjusted to a product thickness of 0.25 mm by stabilization annealing. Table 5 shows the mechanical properties and cap properties.

【table】

[Table] As is clear from Table 5, the No. 1 aluminum alloy plate according to the manufacturing method for deep drawing according to the present invention is more suitable for deep drawing such as caps than the others. It can be seen that it is. Example 3 An ingot produced by manufacturing and casting an aluminum alloy with the ingredients and proportions shown in Table 1 by a normal melting method was soaked at 560°C for 4 hours, and then hot rolled.
3.0 mm (finishing temperature 300°C). After that, rough annealing (350℃×2Hr) and cold rolling were performed, followed by recrystallization treatment at 0.6 mm under the conditions shown in Table 6. Then, cold rolling was performed to a final product thickness of 0.25 mm, and stabilization annealing was performed. Adjusted mechanical properties. Table 6 shows mechanical properties, orientation, crystal grains, and formability.

[Table] It is clear from this Table 6 that the temperature reached (heating temperature after soaking, hot rolling, and cold rolling) is 380
It satisfies the characteristics as a cap in the range of ~500℃, but at temperatures below 380℃ and over 500℃, recrystallization is insufficient or recrystallized grains grow, and the characteristics as a cap are not satisfied. It turns out that you can't do it. As explained above, since the method for manufacturing an aluminum alloy plate for deep drawing according to the present invention has the above configuration, an aluminum alloy plate suitable for caps of whiskey and liquor bottles, etc. can be obtained. It has excellent effects.

Claims (1)

[Claims] 1 Cu0.02~0.1wt%, Fe0.3~1.0wt%, Si0.2~
After soaking, hot rolling, and cold rolling an aluminum alloy ingot containing 0.6, the heating rate and cooling rate are
Aluminum for deep drawing characterized by completing recrystallization by holding at a temperature of 380 to 500°C within 10 minutes at a rate of 100°C/min or more, and then performing finishing cold working at a rolling rate of 30% or more. Method for manufacturing alloy plates.