Improving the Mechanical Properties of a WE54 Magnesium Alloy Through Severe Friction Stir Processing and Rapid Cooling

A commercial WE54 magnesium alloy was severely processed by FSP, lowering heat input, aiming to improve the mechanical properties, both strength and ductility. Additionally, a refrigerated backing anvil was used to warrant rapid cooling and maximize severity. The alloy was processed in two initial tempers, one was the as-received peak-aged T6 temper and the other one, TT, which aimed minimum feasible hardness. The microstructural characterization revealed grain sizes around 1 mu m and high misorientation values. Tensile testing and ultramicroindentation after FSP revealed large strength and ductility improvement for both WE54 tempers. The results presented in the present research show that the mechanical performance of magnesium alloys can be improved by increasing processing severity, making the widespread use of these materials very competitive for the transport industry.