An investigation into wire arc additive manufacturing of Mg-Y-RE-Zr alloy

Abstract

• Mg-Y-rE-Zr alloy without obvious defects is fabricated by WAAM . • Microstructural homogeneity occurs along the deposited direction. • The precipitates of Mg 3 (Nd, Y) and Mg 14 Nd 2 Y are found in the1 st layer. • The bottom part of the deposited wall exhibits a higher hardness. This work fabricates Mg-4Y-3RE-0.5Zr alloy by wire arc additive manufacturing (WAAM). The oxidation inclusion, as one of the main defects in the Y-containing Mg alloys prepared by laser powder bed fusion (LPBF), has not been observed. However, microstructural inhomogeneity along the building height appears due to the combined effect of the different cooling rates of different deposited layers and the subsequent multiple thermal cycles (MTCs). The effect of the microstructural inhomogeneity on the hardness distribution of the deposited wall was also revealed. It is believed that this study provides some new findings to the additive manufacturing of high-performance magnesium rare-earth (Mg-RE) alloys.