About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Fatigue in Materials: Fundamentals, Multiscale Characterizations and Computational Modeling
|
| Presentation Title |
Fatigue Reimagined: Revealing Hidden Deformation Pathways in HEAs |
| Author(s) |
Shreya Mukherjee, Prithvi Awasthi, Priyanka Agrawal, Rajiv Mishra |
| On-Site Speaker (Planned) |
Shreya Mukherjee |
| Abstract Scope |
A comprehensive understanding of cyclic deformation is essential to define fatigue endurance limits in high-entropy alloys (HEAs). In this study, CoCrFeMnNi-based HEAs were first evaluated under stress-controlled fatigue near and above yield strength, where an unexpected increase in fatigue life was consistently observed, challenging conventional behavior. This anomaly motivated strain-controlled fatigue testing to probe underlying mechanisms. Despite deformation-induced martensitic transformation, cyclic stress-strain responses revealed limited hardening, attributed to partial reversibility. These tests uncovered a unique non-monotonic trend in plastic strain accumulation: a sudden rise at intermediate amplitudes followed by suppression at higher amplitudes. This shift coincided with a transition in the strain-life curve from Basquin to Coffin-Manson-dominated behavior, governed by dislocation reversal dynamics. Post-cyclic synchrotron XRD, EBSD, and TEM analyses revealed martensitic banding, stacking fault interactions, and fault-mediated dislocation channels. Weibull statistical modeling was applied to predict the fatigue data and to characterize the variability seen in the HEAs. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
High-Entropy Alloys, Magnetic Materials, Characterization |