Computational studies on BCC superalloys

Abstract

While face-centered cubic (FCC) superalloys have been extensively engineered and optimized, their performance is fundamentally limited by the solvus temperatures of key coherent strengthening precipitates. In contrast, body-centered cubic (BCC) superalloys offer the potential to significantly raise the solvus temperature by incorporating refractory elements. However, the widespread adoption requires overcoming critical challenges, including poor room-temperature ductility, limited creep resistance, and inadequate oxidation performance, which necessitates new alloy design and microstructure optimization. Given the inherent complexity of multicomponent systems, computational tools play a vital role in guiding experimental efforts by screening the massive compositional space in search for potentially ductile BCC and B2 solid solutions, mapping the intricate free-energy landscapes across a high-dimensional space of compositional and processing variables in search for transformation pathways leading to desired microstructures. This viewpoint article summarizes state-of-the-art in computational design of BCC superalloys, and outlines promising future directions in this rapidly evolving field.