Superplastic forging with dynamic recrystallization of Mg–Al–Zn alloys cast by thixo-molding

Grain refinement during forging was found to be due to dynamic recrystallization of four kinds of Mg–x wt.%Al–1 wt.%Zn (x = 3, 4, 5, 6) alloys with grain sizes of ∼30 μm, which were cast using a thixo-molding machine. Superplastic forming combined with forging was successfully performed at a low temperature (473 K) and high-strain rate (3.3 × 10−2 s−1).