Influence of alloying elements on hot tearing susceptibility of Mg-Zn alloys based on thermodynamic calculation and experimental

Based on the hot tearing index |∆T/∆(fs)0.5| recently proposed by Kou and the thermodynamic calculations of Pandat software, Al, Cu, and Mn elements were picked up and their influence on hot tearing susceptibility of Mg-xZn (x = 6, 8, 10, wt%) alloys was studied by experiments. The results indicate that Al addition can significantly reduce the hot tearing susceptibility of Mg-Zn alloys. Either 0.5Cu or 0.3Mn addition individually can reduce the HTS of the Mg-6Zn-(1, 4) Al alloys, while adding together increases the susceptibility. The addition of 0.5Cu and 0.3Mn both individually and together increases the HTS of Mg-8/10Zn-1Al alloys. Based on the experimental and calculation results, the index can be modified to |∆T/∆(fs)0.5|(d)2 for more accurate prediction on the hot tearing resistance of Mg-Zn based alloys. Grain refinement significantly improves the hot tearing resistance of Mg-Zn based alloys.