ENVIRONMENTAL CRACKING OF ADDITIVELY MANUFACTURED 316L STAINLESS STEEL

The widespread use of 316L stainless steel for applications requiring increased corrosion resistance has motivated interest in leveraging additive manufacturing (AM) for in-service production of replacement components. However, while a large number of studies have examined the effect of AM processing parameters on yield strength and fracture toughness, detailed assessments of the environment-assisted cracking (EAC) susceptibility of AM alloys are limited. The objective of this study is to compare the corrosion fatigue and stress corrosion cracking behavior of AM and wrought 316L with similar yield strengths in aqueous chloride environments at temperatures ranging from 293 to 358 K. As built material will be compared with cold drawn bar, and hot isostatic pressed (HIP) material will be compared with plate in the annealed state to minimize the effect of different yield strength between material form. Differences in microstructure and build-introduced stresses are correlated with EAC performance, thereby providing mechanistic insights into the factors governing EAC behavior of AM 316L. In particular, the influence of build direction, residual stresses, texture, and compositional heterogeneities are all assessed.
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