BAKING-COATED AL ALLOY SHEET FOR CAN LID MATERIAL, EXCELLENT IN STRESS CORROSION CRACKING RESISTANCE IN SCORE PART, AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To provide a baking-coated Al alloy sheet for can lid material, improved in SCC resistance without deteriorating strength, such as pressure- resisting strength, and formability, such as rivet formability, and its production. ;SOLUTION: This sheet is a baking-coated Al alloy sheet which has a composition consisting of, by weight, 3.0-5.0% Mg, 0.20-0.70% Mn, 0.01-0.15% Cu, ≤0.35% Fe, ≤0.20% Si, further either or both of 0.01-0.10% Cr and 0.001-0.05% Ti, and the balance Al with inevitable impurities and satisfying Mn/Si≥2.0. Moreover, in the metallic structure in the cross section parallel to the rolling direction, the area fraction of Mg₂Si compound of ≥1μm average grain size is regulated to ≤1.2%, and further, the amount of precipitates of ≥0.1μm average grain size, among Cu-containing precipitates, is regulated to ≤0.040% expressed in terms of Cu.;COPYRIGHT: (C)1997,JPO