Selective laser melting of WC reinforced maraging steel 300: Microstructure characterization and tribological performance

Owing to the limited wear resistance, Maraging steels has limited applications in the harsh environments, leading to a shortened service-life or even failure. In this study, WC particles reinforced maraging steel 300 (MS300) composites were produced by selective laser melting (SLM) to enhance the tribological performance. The microstructure and phase analysis of SLM-produced composites were investigated by SEM-EDS. Dry sliding wear test and microhardness were used to investigate the mechanical properties of WC/MS300 composites. As laser energy density increases, the microhardness drops rapidly and the maximum value of 562.2 HV2 was measured at the linear energy density of 110 J/m. Dry sliding tests show that the wear rate was decreased by > 1500 times through the WC reinforcement compared with pure MS300 sample, which emphasizes the superior wear-resistance properties of MS300/WC composite. Besides, the best wear-resistance performance at the improved linear energy density of 125 J/m. The study on wear mechanism shows that formation of carbide layer between WC and MS300 matrix significantly prevent the plowing effect. The present work provides an effectively method to improve the tribological performance MS300 through the reinforcement of WC particle by selective laser melting.