Effect of internal pores on tensile properties of Co-Cr-Mo alloy fabricated by selective laser melting

Abstract

PurposeThe purpose of this paper is to examine the effect of internal pores on the tensile properties of a Co–Cr–Mo alloy fabricated by selective laser melting (SLM).Design/methodology/approachThe size and volume fraction of pores were controlled through high temperature annealing (HTA) and hot isostatic pressing (HIP).FindingsAfter HTA, the size and fraction of pores decreased compared with the as-built SLM sample, and no pores were observed after HIP. Tensile tests of the HTA and HIP samples showed nearly similar tensile deformation behavior. From the results, the authors found that the size of the internal pores formed in the SLM process had little effect on the tensile properties. The as-built SLM sample had less elongation than the HTA and HIP samples, which would not the effect of porosity, but rather the effect of the residual stress and the retained ε phase after the SLM process.Originality/valueAlthough pores are a main factor that influence the mechanical properties, the effect of pores on the tensile properties of Co–Cr–Mo alloys fabricated by SLM has not been studied. Therefore, in this study, the effect of pores on the tensile properties of a Co–Cr–Mo alloy fabricated by SLM was studied.