Method for manufacturing steel plate for can-making

Abstract

The present invention relates to a method for producing a steel sheet for a can. The steel is continuously cast into a slab, and when finish rolling is performed after rough rolling, the finish rolling is performed at a temperature lower than the Ar3 transformation point by 5% or more of the total rolling amount. And less than 50% of the hot rolling, then, coiling at a coiling temperature of 640 to 750 ° C, pickling, cold rolling at a rolling reduction of 88 to 96%, and then, at more than 400 ° C ~ (recrystallization Annealing is carried out in a temperature range of -20) °C, and the composition of the steel, in terms of mass %, contains C: 0.005% or less, Mn: 0.05 to 0.5%, Al: 0.01 to 0.10%, N: 0.0010 to 0.0070%, B: 0.15×N to 0.75×N (B / N is 0.15 to 0.75), further containing Nb: 4×C to 20×C (Nb / C is 4 to 20), Ti: 2×C to 10×C ( Ti / C is one or both of 2 to 10), and the rest is composed of Fe and inevitable impurity elements. According to this production method, a steel sheet for a can is obtained which has a high strength and ductility required for a can-making process while suppressing the variation in the thickness of the steel sheet coil in the longitudinal direction.

Description

technical field [0001] The present invention relates to a method for manufacturing a steel plate for can making that has high strength and excellent thickness accuracy. Background technique [0002] Cans such as beverage cans, food cans, 18-liter cans, and drum cans can be roughly divided into two-piece cans and three-piece cans according to their manufacturing methods (processes). [0003] The two-piece tank consists of two parts, and is applied to surface-treated steel sheets that have been treated with tin plating, chrome plating, metal oxide coating treatment, chemical conversion treatment, inorganic coating treatment, organic resin coating treatment, and oiling. Shallow drawing processing, DWI processing (Drawing and Wall Ironing Process), DRD processing (Drawing and Redrawing Process) and other processing, the tank bottom and tank body are formed into one, and then the lid is installed on it. [0004] A three-piece can is composed of three parts. Surface-treated steel...

AI Technical Summary

Problems solved by technology

However, in the steel sheet produced under such conditions, there is a problem that the thickness uniformity in the longitudinal direction of the steel sheet coil is degraded.

[0018] In addition, in Patent Document 2 and Patent Document 3, a high-strength steel sheet is obtained by performing annealing without recrystallization, and the hot rolling performed in the Ar 3 40% or 50% or more of rolling is performed below the point. In this case, the strength of TS600MPa to 850MPa targeted by the present invention cannot be obtained even with annealing without recrystallization.

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