Effect of Zn on the microstructure and mechanical properties of Mg–Si alloy

Microstructure and mechanical properties of Mg–0.6Si–xZn alloys (x = 0–1.6 wt%) were investigated to reveal the modification effect of Zn on the morphology of eutectic Mg2Si. It was found 0.5–1.3 wt% Zn effectively modified the morphology of eutectic Mg2Si from laminated structure to fine fiber, and in turn improved significantly the mechanical properties of Mg–Si alloy. Further increase in Zn content changed Mg2Si from fine fiber to Chinese script shape. It was suggested that the Zn content should not exceed 1.5 wt% in Mg–Si–Zn alloy in order to get good mechanical properties.