DIRECT CAST AND ROLLED SHEET EXCELLENT IN MOLDABILITY AND SURFACE QUALITY AND SMALL IN SECULAR CHANGE AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To obtain an Al-Mg-Si series alloy sheet for molding having characteristics equal to those of the conventional one at low cost by simple equipment and process. ;SOLUTION: This direct cast and rolled sheet having 0.7 to 3.0mm sheet thickness is composed of an Al alloy having a compsn. contg. as essential elements, by mass, 0.3 to 2.0% Si and 0.2 to 2.5% Mg, contg. one or ≥ two kinds among 0.01 to 0.5% Mn, 0.01 to 0.5% Cr, 0.01 to 0.5% Zr and 0.001 to 0.5% Ti, moreover contg. one or ≥ two kinds among 0 to 2.0% Cu, 0 to 0.2% Sn and 0 to 2.0% Zn, in which the content of Fe is regulated to ≤0.5%, and the balance Al with inevitable impurities. In this case, the maximum length of continuous crystallized products in the metallic structure of the surface layer part is regulated to ≤50μm.;COPYRIGHT: (C)1998,JPO