| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
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| Symposium
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Advances in Multi-Principal Element Alloys IV: Mechanical Behavior
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| Presentation Title |
Strain-Rate and Temperature Effects on Deformation Behaviors in Body-Centered-Cubic (BCC) Phase Refractory High-Entropy Alloys (RHEAs) |
| Author(s) |
Deva Prasaad Neelakandan, Dongyue Xie, Juntan Li, Chia-Yi Wu, Aomin Huang, Marc A Meyers, Haixuan Xu, Peter K Liaw, Yi-Chia Chou, Ke An, George T Gray III, Nan Li, Gian Song, Saryu J Fensin, Chanho Lee |
| On-Site Speaker (Planned) |
Deva Prasaad Neelakandan |
| Abstract Scope |
The mechanical behavior and microstructural evolution of a single body-centered cubic (BCC) phase NbTaTiV refractory high-entropy alloy (RHEA) were investigated across a wide range of strain rates (10-4 - 103 s-1) and temperatures (room temperature - 850 °C). Compared to conventional alloys, NbTaTiV shows less strain-rate dependence and strong resistance to softening at high temperatures. Interestingly, present NbTaTiV shows an absence of work-hardening behavior under dynamic deformations. These unique plastic deformation behaviors are attributed to the two competing mechanisms, work-hardening by twinning and softening by adiabatic heating). In contrast, significant work-hardening was observed under quasi-static deformation with cryogenic temperatures. This contributed to the formation of "thick" twins at cryogenic temperatures, which act as stronger barriers to dislocation motion, increasing the work-hardening rate during plastic deformation. Density functional theory (DFT) calculations predicted relatively low stacking fault energies and high twinning stress for NbTaTiV, confirming its mechanical resilience. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
High-Entropy Alloys, High-Temperature Materials, Mechanical Properties |