2021/10/07 by Xin Wang, Rafael Rodriguez De Vecchis, Wang, Xin +12
Engineering · Physics and Astronomy · #Advanced materials and composites #Applied Physics (physics.app-ph) #FOS: Physical sciences #High Entropy Alloys Studies #High-Temperature Coating Behaviors #Materials Science (cond-mat.mtrl-sci) #cond-mat.mtrl-sci #physics.app-ph
paper · pdf · doi:10.48550/arxiv.2110.03167
39 pages, 18 figures
openalex publication_date 2021/10/07 · arxiv created 2021/10/11 · openalex created_date 2021/10/11 · arxiv updated 2021/10/12 · openalex updated_date 2026/07/28
Metastable alloys with transformation/twinning-induced plasticity (TRIP/TWIP) can overcome the strength-ductility trade-off in structural materials. Originated from the development of traditional alloys, the intrinsic stacking fault energy (ISFE) has been relied to tailor TRIP/TWIP in high-entropy alloys (HEA), but with limited quantitative success. Herein, we demonstrate a new strategy for designing metastable HEAs and validate its effectiveness by discovering seven new alloys with experimentally observed metastability for TRIP/TWIP. We propose unstable fault energies as the more effective design metric and attribute the deformation mechanism of metastable face-centered cubic alloys to UMFE (unstable martensite fault energy)/UTFE (unstable twin fault energy) rather than ISFE. Among the studied HEAs and steels, the traditional ISFE criterion fails in more than half of the cases, while the UMFE/UTFE criterion accurately predicts the deformation mechanisms in all cases. The UMFE/UTFE criterion provides a new paradigm for developing metastable alloys with TRIP/TWIP for enhanced strength-ductility synergy.