A three-dimensional finite element (F.E.) model is used to estimate the mismatch stresses at a microscopic scale in γ-γ' single-crystal nickel-based superalloys. F.E. calculations point out the specificity of stress/strain distributions in these alloys, in particular the fact that internal stresses concentrate in the connected γ matrix. The analysis of stress/strain fields and elastic energy evolution as a function of precipitate morphology and volume fraction allows to explain some atypical precipitate shape changes such as "splitting" during precipitation treatments or "raftening" during high temperature creep tests.
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