The high strength and hydrogen embrittlement resistance of selective laser melted 304 austenitic stainless steel

3D printing technology can be used to produce a variety of complex parts for hydrogen service. In this study, 304 austenitic stainless steel (ASS) sample was manufactured by selective laser melting (SLM), one of the 3D printing technologies, then its high strength and hydrogen embrittlement resistance were discovered in comparison to traditional solution-treated 304 ASS. The unique high-density dislocation cellular structure of SLM sample remarkably restrained the nucleation of alpha'-martensite and slowed down the diffusion of hydrogen. Moreover, the possibility of hydrogen induced intergranular fracture was significantly reduced because of the alleviated hydrogen segregation at the grain boundary.

Automated summary

3D printing technology is capable of producing complex parts for hydrogen service. In this study, a 304 austenitic stainless steel (ASS) sample was manufactured using selective laser melting (SLM), a 3D printing technology. The SLM sample exhibited higher strength and resistance to hydrogen embrittlement compared to traditionally solution-treated 304 ASS. This was attributed to the unique high-density dislocation cellular structure of the SLM sample, which hindered alpha'-martensite formation and slowed down hydrogen diffusion. Additionally, hydrogen-induced intergranular fracture was reduced due to alleviated hydrogen segregation at the grain boundary.