Towards stacking fault energy engineering in FCC high entropy alloys
Khan, Tasneem Z.
Iowa State University Digital Repository, Ames IA (United States)
Is Version Of
Materials Science and EngineeringChemical and Biological EngineeringAmes LaboratoryPhysics and Astronomy
Stacking Fault Energy (SFE) is an intrinsic alloy property that governs much of the plastic deformation mechanisms observed in fcc alloys. While SFE has been recognized for many years as a key intrinsic mechanical property, its inference via experimental observations or prediction using, for example, computationally intensive first-principles methods is challenging. This difficulty precludes the explicit use of SFE as an alloy design parameter. In this work, we combine DFT calculations (with necessary configurational averaging), machine-learning (ML) and physics-based models to predict the SFE in the fcc CoCrFeMnNiV-Al high-entropy alloy space. The best-performing ML model is capable of accurately predicting the SFE of arbitrary compositions within this 7-element system. This efficient model along with a recently developed model to estimate intrinsic strength of fcc HEAs is used to explore the strength–SFE Pareto front, predicting new-candidate alloys with particularly interesting mechanical behavior.
This is a manuscript of the article Khan, Tasneem Z., Tanner Kirk, Guillermo Vazquez, Prashant Singh, A. V. Smirnov, Duane D. Johnson, Khaled Youssef, and Raymundo Arróyave. "Towards stacking fault energy engineering in FCC high entropy alloys." Acta Materialia 224 (2022): 117472. DOE Contract Number(s): DOI: 10.1016/j.actamat.2021.117472. Copyright 2021 Acta Materialia Inc. DOE Contract Number(s): AC02-07CH11358; DGE-1545403; DEMS-1663130; DMREF-1729350. Posted with permission.