Designing order–disorder transformation in high-entropy ferritic steels.
Iowa State University Digital Repository, Ames IA (United States)
Is Version Of
Materials Science and EngineeringChemical and Biological EngineeringAmes National LaboratoryPhysics and Astronomy
Order–disorder transformations hold an essential place in chemically complex high-entropy ferritic steels (HEFSs) due to their critical technological application. The chemical inhomogeneity arising from mixing of multi-principal elements of varying chemistry can drive property altering changes at the atomic scale, in particular short-range order. Using density-functional theory-based linear-response theory, we predict the effect of compositional tuning on the order–disorder transformation in ferritic steels—focusing on Cr–Ni–Al–Ti–Fe HEFSs. We show that Ti content in Cr–Ni–Al–Ti–Fe solid solutions can be tuned to modify short-range order that changes the order–disorder path from BCC-B2 (Ti atomic-fraction = 0) to BCC-B2-L21 (Ti atomic-fraction > 0) consistent with existing experiments. Our study suggests that tuning degree of SRO through compositional variation can be used as an effective means to optimize phase selection in technologically useful alloys.
This article is published as Singh, Prashant, and Duane D. Johnson. "Designing order–disorder transformation in high-entropy ferritic steels." Journal of Materials Research 27 (2022): 136-144. DOI: 10.1557/s43578-021-00336-w. Copyright 2021 The Author(s). Attribution 4.0 International (CC BY 4.0). DOE Contract Number(s): AC02-07CH11358. Posted with permission.