Superplastic deformation characteristics and constitution equation in rapidly solidified Mg–Al–Ga alloy

The hot deformation characteristics of a newly typed, high strength magnesium-based alloy, Mg–8.3 wt.% Al–8.1 wt.% Ga alloy, produced by rapidly solidified and powder metallurgy method have been investigated. Tensile tests were carried out at a temperature range from 523 to 623 K and a strain rate range from 10⁻⁴ to 1 s⁻¹. Superplastic characteristics were found and, especially, a maximum elongation-to-failure of 1080% was obtained at 573 K and at a relatively high strain rate of 10⁻² s⁻¹. Because of the presence of fine microstructures at high temperatures, the optimum superplastic strain rate of the Mg–Al–Ga alloy was higher than that of the reported conventional superplastic aluminum and magnesium alloys.