| 摘要 |
PURPOSE:To improve the can openability and cap workability of a titled steel plate by keeping the ratio of the cold rolled recovered structure of a steel plate having undergone heat treatment after cold rolling at more than specific rates. CONSTITUTION:When a steel plate having been subjected to cold rolling is heated and annealed, the steel plate softens while releasing cold working strains with a rise in temp., and the steel plate structure successively changes to cold rolled structure, cold rolled recovered structure and recrystallized structure. In the intermediate heating temperatures or heating time, these structures mingle. The steel plate having the structure in which the soft recrystallized structure and the relatively hard cold rolled recovered structure mix or the cold rolled recovered structure of different degrees of relieving of cold rolling strains has low can opening strength and good cap workability. Hence, this steel plate for easy-to-open can caps consists of the mixed structure of the cold rolled recovered structure and the recrystallized structure and the ratio of its cold rolled recovered structure is made to >=5% of the entire part in area rate. |
