Hot corrosion behaviour of Inconel 625 weldments in molten lithium salt

Abstract

In this study, the hot corrosion behaviour of Inconel 625 weldments in a molten lithium salt (LiCl–1 wt-%Li₂O) was investigated at 650°C. The hot corrosion behaviour was observed through measurements of the oxide morphology, attack depth and compositional changes of the weldment. The corrosion products of as received (W625) and post-weld heat treated specimens (W625H) under isothermal load were Li₄MoO₅ and NiFe₂O₄, while FeNi₃, Li₄MoO₅ and NiFe₂O₄ were identified as the corrosion products of as received cyclic specimens under cyclic heat load. The difference in weight loss between W625 and W625H was negligible, whereas very low weight loss was observed in cyclic specimens (W625C).

Keywords

Hot corrosion Molten salts Reactor conditions Superalloys

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