| 摘要 |
PURPOSE: To easily obtain an alloy sheet capable of executing practical super plastic forming without adopting special condition by specifying the temp. and strain rate at forming of the alloy sheet regulated for grain size with specified composition. CONSTITUTION: The aluminum alloy sheet contains, by weight, 3.5-8.5% Mg, <=0.5% Cu, <=0.15% Si, <=0.15% Fe, and further, one or more kinds among <=0.4 Mn, <=0.1% respective Cr, Zr, V and Ti respectively, <=0.01% B, and the balance Al, and it is constructed with an average grain size of 15-120μm. The sheet is formed at a strain rateεof >=10<-4> /sec<-1> and at a forming temp. T of 523-823K while the strain rateεand forming temp. T are in the range of the equation: 1nε<-160+24.5lnT. By this method, an elongation of 200% or more is attained so as to make superplastic forming possible. |
