HR-2 is a single-phase austenitic stainless steel with excellent hydrogen embrittlement resistance and a wide range of applications in hydrogen storage pressure vessels. During the powder preparation and additive manufacturing process, burning nitrogen deteriorates its hydrogen embrittlement resistance and mechanical properties. In this paper, HR-2 stainless steel powder was prepared by vacuum induction melting atomization (VIGA), and the HR-2 powder with acceptable nitrogen content was obtained in a nitrogen atmosphere. The effects of process parameters in selective laser melting, including laser energy density on the part density, microstructure, and mechanical properties of the formed specimens, were investigated. The results show the density of the formed samples first increase and then decrease as the energy density increases. With the optimization of process parameters, the density of the parts fabricated by SLM formed HR-2 with low nitrogen can reach more than 99.5%, the tensile strength can reach 735 ± 5 MPa, the yield strength can reach 415 ± 10 MPa, the percentage elongation of 43 ± 5%, and percentage reduction of 44 ± 5%, while the tensile strength of HR-2 with high nitrogen can reach 720 ± 10 MPa, the yield strength can reach 603.5 ± 10 MPa, the percentage elongation of 45 ± 5%, and percentage reduction of 60 ± 5%, which are comparable with the base material of forged HR-2.
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