Effect of Pd on microstructures and tensile properties of as-cast Mg–6Al–1Zn alloys

The effects of Pd on the microstructure and mechanical properties of Mg–6Al–1Zn alloys were investigated. Mg–6Al–1Zn–xPd (x = 0–6 wt.%) alloys were prepared using a permanent mould casting method. The microstructure of the as-cast alloys was characterized by the presence of Mg17Al12 and Al4Pd phases. The volume fraction of the Al4Pd phase was increased by the addition of 1–6 wt.%Pd but the volume fraction of the Mg17Al12 phases decreased. At room temperature, the tensile strength increased with increasing Pd addition up to 2 wt.%Pd, and the elongation to fracture decreased with a concomitant increase in the aggregation of the coarse Al4Pd phase. At 150 °C, the tensile strength increased with the addition of Pd. Therefore, the room and elevated temperature tensile properties of as-cast Mg–6Al–1Zn alloys can be improved by Pd addition.

Graphical AbstractThe microstructure of as-cast alloys was characterized by the presence of Mg17Al12 and Al4Pd phases. The volume fraction of the Al4Pd phase was increased but Mg17Al12 phases were decreased by adding 1–6 wt.%Pd. The tensile strength increased up to 2 wt.%Pd and the elongation to fracture decreased with an increase in the aggregation of the coarse Al4Pd phase present in each alloy at room temperature.Figure optionsDownload as PowerPoint slide