(27-0224)Strength Prediction of Ni-base Disc Superalloy: Modelling of Gamma Prime Strengthening

摘要

Accurate extraction of the multiple strengtheningmechanisms in polycrystalline Ni-base superalloy with γ-γ' dualphase is necessary for the processing optimization suitable for use asturbine disc in aerospace engine [1]. Currently reported predictionmodels cannot fully describe the inverse-temperature dependence ofstrength due to the lack of consideration hardening by rule of mixture(ROM) [2]. To verify the strength contribution from γ' mixture rule,critical resolved shear stress (CRSS) values were measured for aseries of dual phase single crystal tie-line modeling alloys based onthe commercial U720Li compositions (Fig 1). Further, we discussedthe prediction method suitable within a grain of U720Li superalloys.