Microstructure and mechanical properties of Mg–4Al–4Nd–0.5Zn–0.3Mn alloy

Mg–4Al–4Nd–0.5Zn–0.3Mn alloy was prepared by metal mould casting method. Microstructure, aging behavior, mechanical properties and fracture morphology of the alloy were investigated. The results showed that α-Mg, Al11Nd3, Al2Nd and Mg32(Al,Zn)49 phases were the main phases of the as-cast alloy. And the long rod-like Al11Nd3 phase was decomposed to granular Al2Nd through T6 heat treatment. The tensile strength was also enhanced by T6 treatment. The yield strength was increased by 17% and 21% at RT and 150 °C, respectively. It was mainly because that the precipitates were refined through T6 treatment and this became more benefit to hinder dislocations slipping.