PURPOSE: To improve the stress corrosion-cracking resistance, strength, and weldability of an aluminum alloy by adding specified amounts of Au, V and rare earth elements or misch metal to an Al-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, 0.01 to 0.2% V, and the balance Al with inevitable impurities. Furthermore, one or more kinds among 0.01 to 1.5% Mn, 0.06 to 0.1% Cr, 0.01 to 0.25% Zr, 0.0001 to 0.08% B, and 0.03 to 0.5% Mo are incorporated therein. This alloy has high strength as the material for welded structures and excellent in formability in extruding, rolling, forging or the like.
MATSUOKA KEN
KATO KAZUMI
MURATA FUJIO
