Comparative study of microstructure and texture of cast and homogenized TX32 magnesium alloy after hot deformation

The effect of homogenization on the hot deformation behavior and texture evolution of Mg-3Sn-2Ca (TX32) alloy is investigated. The cast-homogenized alloy samples were hot compressed in the temperature and strain rate ranges of 300–500 °C and 0.0003–10 s⁻¹, respectively, and a processing map has been developed by using the flow stress data. The map revealed two dynamic recrystallization (DRX) domains with a peak efficiency of 44% at 360 °C/0.0003 s⁻¹ (Domain 1) and 43% at 485 °C/0.1 s⁻¹ (Domain 2). When compared with the map for as-cast condition, it is observed that both the domains moved towards higher temperatures although the shift of Domain 1 is more noticeable. The apparent activation energy values in the two domains and the regime of flow instability are nearly unchanged by homogenization, suggesting that Mg₂Ca and CaMgSn particles in the microstructure are thermally stable. Specimens deformed under conditions in Domain 1 have high Schmid factors for {0001} (Formula presented.) basal slip and (Formula presented.) prismatic slip, while in Domain 2 the deformation progressed due to (Formula presented.) second-order pyramidal slip.