Effects of grain refinement methods on microstructure and mechanical properties of AM60 magnesium alloys

Several kinds of grain refinement processes for Mg-Al series alloy were surveyed. Effects of C2Cl6 on the composition, density, microstructure and mechanical properties of the AM60 alloy were investigated by XRF spectrometer, optical microscope, Brinell hardness tester, electronic balance and MTS material testing machine etc. The results show that C2Cl6 has good effects on grain refinement, greatly improving the mechanical properties of the AM60 alloy castings. Compared with those of the alloy free C2Cl6, the grain size of as-cast AM60 alloy with the optimum addition of 1% C2Cl6 can be decreased from 250 μm to 70 μm, and tensile strength is 237 MPa and elongation is 18.9%, increased by 11.3% and 65.8%, respectively. Furthermore, the mechanisms of grain refinement and strengthening of Mg-Al series alloy with C2Cl6 were approached.