Influence of micro-alloying with Cd on growth pattern, mechanical properties and microstructure of as-cast Mg94Y2.5Zn2.5Mn1 alloy containing LPSO structure

The effects of Cd addition on the microstructure and mechanical properties of Mg94Y2.5Zn2.5Mn1 alloy containing alpha-Mg matrix, W phase and 18R LPSO structure were systematically explored first. The results reveals that trace of Cd can refine alpha-Mg grain size and facilitate the formation of 18R LPSO structure efficiently, but suppress the growth of W-phase significantly. Moreover, the growth pattern of LPSO structure and W phase are changed from the coupled growth to divorced growth due to the Cd addition. The as-cast Mg94Y2.5Zn2.5Mn1Cd0.35 alloy exhibits the remarkable ultimate tensile strength (247 MPa) and outstanding elongation (16.5%), which is attributed to plentiful LPSO phase, grain refinement and transformation of growth pattern.