HIGH-STRENGTH STEEL SHEET FOR CONTAINER AND PROCESS FOR PRODUCTION THEREOF

摘要

Provided are a steel sheet for a container which has hardness of 500MPa or above and excellent workability, and a process for the production of the sheet. A high-strength steel sheet for containers which has a tensile strength of 500MPa or above and in which the proof stress difference between the sheet widthwise direction and the rolling direction is 20MPa or below can be obtained by subjecting a steel which contains by mass C: 0.01 to 0.05%, Si: 0.04% or less, Mn: 0.1 to 1.2%, S: 0.10% or less, Al: 0.001 to 0.100%, N: 0.10% or less, P: 0.0020 to 0.100% with the balance being Fe and unavoidable impurities to hot rolling at a finishing temperature not lower than the Ar3 transformation temperature minus 30 (°C) and a coiling temperature of 400 to 750°C, subjecting the rolled steel to pickling, cold rolling, and then continuous annealing including over-aging, and then subjecting the resulting sheet to second cold rolling with a draft of 20 to 50%.