|About this Abstract
||MS&T22: Materials Science & Technology
||High Entropy Materials: Concentrated Solid Solutions, Intermetallics, Ceramics, Functional Materials and Beyond III
||Deformation Behaviors and Mechanisms in Single BCC Phase Refractory High-entropy Alloys
||Chanho Lee, George Kim, Yi Chou, Michael C Gao, Ke An, Gian Song, Yi-Chia Chou, Wei Chen, Nan Li, Saryu Fensin, Peter K Liaw
|On-Site Speaker (Planned)
Single-phase solid-solution refractory high-entropy-alloys (RHEAs) show remarkable mechanical properties, such as high yield strength with significant resistance to softening at elevated temperatures. To understand the original of this high strength, it is important to investigate the deformation and strength mechanisms via an in-depth study. We have investigated the elastic- and plastic-deformation behaviors of two BCC NbTaTiV and NbTaTiVZr RHEAs, using both experiments and simulations. The in-situ neutron-diffraction results reveal that there is a transition in the load-bearing capability of the grains from isotropic to anisotropic at elevated temperatures. Furthermore, we have systematically and quantitatively determined lattice distortion using a theoretical model, first-principles calculations, synchrotron X-ray/neutron diffraction, and scanning-transmission-electron microscopy techniques. These results demonstrate that severe lattice distortion is a core reason for high strengths in RHEAs.