An investigation on hot-cracking mechanism of Sr addition into Mg-6Al-0.5Mn alloy

The hot-tearing susceptibility of Mg–6Al–0.5Mn alloy decreased with the increasing Sr content (≤0.2 wt%). The related mechanism is described as follows: Sr refines the grain and reduces the tendency of divorced eutectic; Sr decreases the eutectic temperature and results in higher intergranular strength. Both of the above reasons could improve the filling capacity of the melt, resulting in the best hot-tearing-resistant property of the alloy.