Effects of Sc and Mn on microstructures and mechanical properties of Mg-Gd alloy

摘要

Two alloys of Mg-12.4Gd and Mg-12.5Gd-0.8Sc-1.4Mn were prepared. Hot extrusion and T5 heat treatment were conducted,and then the mechanical properties of the two alloys were tested at room and high temperatures. The effects of Sc,Mn on the microstructures of Mg-12.4Gd were investigated by optical microscopy,scanning electron microscopy and transmission electron microscopy. The results demonstrate that after hot-extrusion the alloying with Sc,Mn can efficaciously refine the grains of Mg-12.4Gd alloy;and increase the elongation at room and high temperatures after T5 heat treatment. But the strength at high temperature is not obviously improved.