Microstructure and properties of a nano-ZrO₂-reinforced AlSi10Mg matrix composite prepared by selective laser melting

In this study, nano-ZrO₂-reinforced AlSi10Mg composites were prepared using a high-speed homogenizer and samples were fabricated by selective laser melting (SLM) technique. The effects of ZrO₂ on the microstructures, crystallographic textures and mechanical properties of the ZrO₂/AlSi10Mg composites were studied. The results show that ZrO₂ particles were distributed uniformly and had good interfacial bonding with the AlSi10Mg matrix. The incorporation of ZrO₂ reduced the formation of large crystalline grains and had an important role in grain refinement. The small-angle grain boundaries and (001) crystal orientation were greatly enhanced. Compared with AlSi10Mg, ZrO₂/AlSi10Mg had superior mechanical properties, including the highest hardness strength of 139 HV (an average increase of 10.3%), a tensile strength of 478.6 MPa and an elongation of 10.6% (increases of 13.5% and 41%, respectively).