Composition and Heat Treatment Modifications of a New Low-Cost Ni Base Wrought Alloy for Improved Creep Resistance and Elevated Temperature Ductility

Exp-G27 is a new low-cost Ni base wroughtWrought alloy developed by Carpenter Technology Corporation for applications such as jet engineJet engines turbine casing and internal combustion engine exhaust valves. Mainly strengthened by γ’, Exp-G27 has higher temperature stability compared to alloy 718. Within the targeted service temperature range between 704 and 871 °C, Exp-G27 demonstrates comparable mechanical performance as WaspaloyWaspaloy but with a significantly lower raw material cost. However, the creepCreep and stress ruptureStress rupture of Exp-G27 is slightly lower than WaspaloyWaspaloy. In this study, a cost-performance tradeoff study was carried out to help make modification to the original Exp-G27 to achieve superior creepCreep/stress ruptureStress rupture performance than WaspaloyWaspaloy while still being cost competitive.