Mechanical properties of selective laser melted ZK60 alloy enhanced by nanoscale precipitates with core-shell structure

The magnesium alloy of ZK60 components manufactured by selective laser melting (SLM) have been investigated in this work. The microstructure and the mechanical properties of the SLM-processed samples are determined. The ZK60 samples prepared had fish-scale features along the build direction along with homogeneous and refined grains. The microstructure consisted of equiaxed α-Mg matrix with a size of 3–8 μm and nanoscale precipitates. The nano-precipitates had a core-shell structure with a Zn₂Zr core embedded in a MgZn₂ shell. The optimal micro-hardness and the compressive yield strength of the SLM ZK60 sample at room temperature are 90 Hv and 172.59 MPa, respectively, which is superior to cast ZK60 because of grain refinement strengthening and precipitation strengthening.