On the effect of alloying additions to the Ni-Cr-Al-Nb dual-superlattice gamma-gamma prime-gamma double prime superalloys

Abstract

Recent work has identified a novel Ni-Cr-Al-Nb alloy capable of generating a γ-γ′-γ″ dual-superlattice microstructure with excellent microstructural stability and tensile strength. In this study, we report on the effect of additions of alloying elements that traditionally partition to the γ matrix. Attention is focussed on their effects upon the microstructure, hardness and lattice misfit of dual-superlattice superalloys. The results obtained from these studies indicate that judicious alloying may further enhance the properties and stability of these dual-superlattice superalloys and that they offer the potential of greatly increased temperature capability compared to other alloys reinforced by γ″ precipitates