Microstructure and Mechanical Behavior of Co@Al2o3/Cocrmo Composites Fabricated by Selective Laser Melting

Abstract

In this study, cobalt coated alumina (Co@Al2O3) particles were prepared via the electroless plating process, and mixed with CoCrMo alloy powders in the proportion of 0.5 wt.% to 2 wt.%. The Co@Al2O3/CoCrMo composites were then manufactured by selective laser melting (SLM) process. The microstructure, wear resistance performance and mechanical property of the composites were characterized. By increasing the content of Co@Al2O3 particles from 0.5 wt.% to 1.0 wt.%, the composites kept flawless with the lowest wear rate of 2.07◊10-5 mm3‧N-1‧m-1 and the highest ultimate tensile strength (UTS) of 1251.93 MPa. When the content of Co@Al2O3 particles increased further, both the wear rate and UTS of composites deteriorated unexpectedly, which could be ascribed to the micrometer-scale pores from the gasification of organic matter in Co@Al2O3 particles during the SLM process.

Keywords: selective laser melting, CoCrMo alloy, alumina, electroless plating, mechanical property