An investigation on solidification path and hot tearing tendency of Mg−2Zn−3Y−xAl alloys

Abstract

AbstractBased on the improved Clyne‐Davies’ model (CSCT), the hot tearing tendency of Mg−2Zn−3Y−xAl (x = 0, 0.5, 1, 2, wt.%) alloys were predicted. The concretion path, the solidification characteristic temperature, the dendrite coherent solid fraction were studied by the double thermocouples thermal analysis. The curve of solidification contraction stress with temperature (or time) was measured with a “T” type hot tearing permanent‐mold. The experimental results show that the modified Clyne‐Davies’ model prediction values are in good agreement with the experimental results. Al2Y phase can be used as the heterogeneous nucleation core of α‐Mg matrix and refine the α‐Mg grain size. It is found that Al2Y increases, grain refinement is more obvious, dendrite coherence is postponed, and the hot tearing susceptibility of the alloy decreases significantly with increasing aluminum content.