Effect of Sb on Microstructure and Mechanical Properties of Mg2Si/Al-Si Composites

Abstract The effect of Sb on the microstructure and mechanical properties of Mg 2 Si/Al-Si composites was investigated. The results show that Sb can improve the microstructure and mechanical properties of Mg 2 Si/Al-Si composites. When the content of Sb is 0.4%, the morphology of primary Mg 2 Si changes from dendrites to fine particles, the average size of Mg 2 Si particles is refined from 52 to 25 μm, and the ultimate tensile strength and elongation of the composites increase from 102.1 MPa and 0.26% to 138.6 MPa and 0.36%, respectively. The strengthening mechanism can be attributed to the fine-grain strengthening. However, excessive Sb is disadvantageous to the modification of the composites.