Influence of hydrogen on electrochemical behavior of Ni-based superalloy 718

Grégory Odemer (1) , Eric Andrieu (1) , Christine Blanc (1)

1 CIRIMAT - Centre interuniversitaire de recherche et d'ingenierie des matériaux

Numerous studies have shown that Ni-based superalloy 718 may be sensitive to hydrogen embrittlement and have highlighted the dominant roles played by the hydrogen solubility and the hydrogen trapping. Samples were hydrogenated by cathodic polarization in molten salts under different conditions to vary the diffusible hydrogen content and to saturate the different hydrogen traps present in the microstructure strengthened by precipitation. Open circuit potential and galvanic coupling measurements were conducted in order to characterize the effect of diffusible and trapped hydrogen on electrochemical behavior and to discuss the possibility of galvanic coupling between zones with different hydrogen contents.

Mots clés: Nickel alloys; Hydrogen embrittlement; Electrochemistry; Galvanic coupling

Domaines: Génie chimique; Génie des procédés

Grégory Odemer, Eric Andrieu, Christine Blanc. Influence of hydrogen on electrochemical behavior of Ni-based superalloy 718. International Journal of Hydrogen Energy, 2018, 43 (2), pp.1006-1011. ⟨10.1016/j.ijhydene.2017.11.081⟩. ⟨hal-01991073⟩