Crack Path and Liquid Metal Embrittlement Specificity of Austenitic Steels in Mercury at Room Temperature

A liquid metal embrittlement specificity of three austenitic steels with increasing nickel content (304L, 316L and 316L(N)) is studied in mercury. Only the low alloys are susceptible to LME. The crack path an steel fracture induced by mercury has been elucidated. Deformation martensite (γ → α’) induces numerous α’/α’ interfaces at small scale that be embrittled. Because only resists LME one shows stability over a’ phase change due mostly its higher content, a point confirmed X Ray fractography, it inferred major factor contributing sensitivity room temperature α’ formation unstable during plastic strain. This provides sound rationale on how prevent steels.