Microstructural and Thermomechanical Assessment of Computationally Designed Ni-Based SX Superalloys

Five computationally designed single crystal superalloysSingle crystal superalloy have been developed for aircraft engine airfoils submitted to high temperaturesHigh temperature. The broad steps of the alloy designAlloy design procedure are presented in this study. Tensile and creep propertiesCreep properties of these SX superalloysSuperalloys are evaluated in regard to the predictions of the creepCreep-life model and/or in regard to reference SX superalloysSuperalloys. Effective and predicted density show a good consistence. The γ′ phase fraction predicted by CALPHADCALPHAD calculations at the designDesign stage and the ones evaluated in this work are consistent as well. For AMSP2 alloy, atom probe tomographyAtom probe tomography measurements were conducted. We observe that excessive additions of rhenium to a platinumPlatinum containing SX superalloySuperalloys have a strong impact on creep propertiesCreep properties, reducing the creepCreep lifetime compared to the reference alloy TROPEA, and strongly affect the γ/γ′ coherency, leading to the absence of raftingRafting at intermediate temperatures (950–1050 °C).