| 摘要 |
PROBLEM TO BE SOLVED: To obtain an Al alloy sheet for a PP (pilfer proof) cap having satisfactory cap openability in spite of its extremely high strength, having satisfactory earing rates, free from curving of a printing character and having excellent surface quality as well. SOLUTION: The Al alloy sheet comprises >3.0 to 5.0% Mg, 0.1 to 0.3% Fe, 0.05 to 0.5% Mn and 0.05 to 0.2% Si, and in which the area ratio of all crystallized products is 1.0 to 2.0%, and tensile strength is 300 to 350 MPa. Regarding its production method, hot finish rolling is performed under the conditions satisfying a starting temperature of≤450°C, a finishing temperature of 260 to 330°C, the total draft of≥85% and a draft in the final pass of≥40%, thus the hot rolled sheet is made into a recrystallized state, next, primary cold rolling is performed, thereafter, process annealing is performed at 400 to 550°C without performing holding or under holding within 2 min, then, finish cold rolling is performed at the total draft of 25 to 50%, and next, stabilization treatment is performed. COPYRIGHT: (C)2007,JPO&INPIT
|
