Comparison of wear behavior of GCr15 bearing steel prepared by selective laser melting (SLM) and electron beam melting (EBM)

[Display omitted] •The friction resistance of GCr15 bearing steel prepared by SLM and EBM was investigated.•The size of the grain of GCr15 bearing steel prepared by EBM is significantly reduced.•Nano-cementite significantly increases the wear resistance of GCr15 bearing steel. Both the microstructure and wear behavior of GCr15 bearing steel prepared by selective laser melting (SLM) and electron beam melting (EBM), respectively, are compared for the first time in this study. The results show that the microstructure of SLMed-GCr15 bearing steel is composed of residual austenite and fine martensite and EBMed-GCr15 bearing steel is mainly globular pearlite, the globular cementite precipitated in the ferrite surface is fine (80 ~ 400 nm) and uniformly distributed. The Vickers hardness of the samples prepared by SLM is 750.0±17.1 HV0.2, the coefficient of friction (COF) and wear rate are 0.5082 and 24.6±3.2 μm3N−1m−1, respectively, and the wear mechanism is mainly adhesive wear. The sample prepared by EBM has the lowest COF and wear rate, which is 0.4647 and 18.4±1.7 μm3N−1m−1, respectively, and the wear mechanism is mainly abrasive wear and adhesive wear, which shows excellent friction resistance.