Effects of scanning speeds on the wear behavior of CoCrW alloy fabricated by selective laser melting

Scanning speed effects on the microstructural evolution and wear properties of CoCrW alloy manufactured by selective laser melting (SLM) technology were investigated in this work. Results demonstrated that the defect size tends to increase with the increased scanning rate and counterparts fabricated under a higher scanning rate (i.e., 1200 mm/s) show typical lack-of-fusion defects due to the insufficient fusion process. Microstructural characterization showed that the cellular structure of SLM CoCrW alloy grows along the direction perpendicular to the molten pool boundary. The wear mechanism of SLM CoCrW alloy at room temperature is abrasive wear and the friction coefficient of the SLM CoCrW alloy FD-SD plane is slightly larger than that of the BD-SD plane. The wear rate of the FD-SD plane is greater than that of the BD-SD plane. The good wear properties for the BD-SD plane are mainly due to the fine cellular structure.