HIGH STRENGTH ALUMINUM ALLOY FOR WELDING EXCELLENT IN STRESS CORROSION-CRACKING RESISTANCE

摘要

PURPOSE:To improve the stress corrosion cracking resistance, strength, and weldability of an aluminum alloy by adding specified amounts of Au and rare earth elements or misch metal to an Au-Zn-Mg-Cu series alloy. CONSTITUTION:The compsn. of a high strength Al alloy for welding is formed of, by weight, 5 to 8% Zn, 1.2 to 4.0% Mg, 1.5 to 4.0% Cu, 0.03 to 1.0% Au, 0.03 to 5.0% rare earth elements or misch metal, 0.01 to 1.0% Fe 0.005 to 0.2% Ti, and the balance Al with inevitable impurities. Furthermore, one or more kinds among 0.01 to 1.5% Mn, 0.01 to 0.6% Cr, 0.01 to 0.25% Zr, 0.0001 to 0.08% B, and 0.03 to 0.5% Mo are incorporated therein. Au improves its stress corrosion-cracking resistance and strength. This alloy has high strength as the material for welded structures and excellent in formability in extruding, rolling, forging or the like.