PURPOSE: To obtain a high specific strength Al alloy having good fluidity by subjecting an alloy having the specified compsn. constituted of Li, Cu, Mg, Si, Zr, Ti, B, Fe and Al to specified solution treatment and thereafter executing specified aging treatment.
CONSTITUTION: An alloy constituted of, by weight, 2.0 to 2.7% Li, 2.5 to 3.5% Cu, 0.1 to 0.3% Mg, 0.1 to 0.2% Si, 0.1 to 0.3% Zr, 0.05 to 0.15% Ti, 0.001 to 0.020% B, ≤0.12% Fe and the balance Al is subjected to solution treatment at 515±10°C for 14±4hr. After that, this alloy is subjected to aging treatment at 200±5°C for 6±2hr. By this heat treatment, the high specific strength Al alloy having about ≥17.5×103 specific strength and combining good fluidity and elongation can be obtd.
TANAKA TORU
MATSUDA KENJI
