| 摘要 |
PURPOSE:To produce a high tensile Al-Li alloy for superplastic forming having high strength and high elongation by subjecting an ingot of an alloy in which specific percentages of Li, Cu, Mg, and Zr are incorporated to Al to precipitation treatment under specific conditions. CONSTITUTION:An ingot of an alloy having a composition consisting of, by weight, 2.80-4.00% (not including 2.80%) Li, 0.80-2.50% Cu, 0.50-1.80% Mg, 0.08-0.20% Zr, and the balance Al with inevitable impurities is subjected to precipitation treatment at 220-400 deg.C for 1-100hr. By this method, the high tensile Al-Li alloy in which structure is homogenized and workability and elongation are improved and which shows strength and elongation superior to those of seven thousand series Al alloy by means of proper ageing treatment after superplastic forming is performed. |
