Effects of antagonistic interaction between Cr and Ni on hydrogen solubility in a Fe-Cr-Ni ternary austenitic system; A First-principles calculation

Moriyama, Junichiro*; Yamaguchi, Masatake   ; Takakuwa, Osamu*

The present study systematically investigates hydrogen (H) solubility within multi-component alloying (Cr, Ni) interaction in Fe-Cr-Ni-based austenitic alloys, which generates a novel H-induced improvement in the strength-ductility balance that is a function of dissolved H-content. We analyzed, using first-principles calculations, H-absorption energy that is directly linked to H-solubility, in an Fe-Cr-Ni face-centered cubic (FCC) ternary system with various configurations of Cr and Ni atoms. The results we obtained clarified the effects of antagonistic interactions between Cr and Ni atoms on H-absorption energy even though both alloying elements independently reduce H-absorption energy at adjacent octahedral sites (O-sites). The present study makes it possible to comprehensively predict the H-solubility of various Fe-Cr-Ni austenitic alloys by taking account of the antagonistic Cr-Ni interaction.