About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
|
Local Ordering in Materials and Its Impacts on Mechanical Behaviors, Radiation Damage, and Corrosion
|
Presentation Title |
Multi-scale Investigation of Chemical Short-range Order and Dislocation Glide in the MoNbTi and TaNbTi Refractory Multi-principal Element Alloys |
Author(s) |
Shyue Ping Ong, Hui Zheng, Lauren T. W. Fey, Xiang-Guo Li, Yong-Jie Hu, Liang Qi, Shuozhi Xu, Irene Beyerlein |
On-Site Speaker (Planned) |
Shyue Ping Ong |
Abstract Scope |
Refractory multi-principal element alloys (RMPEAs) are promising materials for high-temperature structural applications. In this talk, I will discuss the role of chemical short-range ordering (CSRO) on dislocation glide in two RMPEAs --- TaNbTi and MoNbTi --- using a multi-scale modeling approach. We show that MoNbTi exhibits a much greater degree of SRO than TaNbTi and the local composition has a direct effect on the unstable stacking fault energies. From mesoscale phase-field dislocation dynamics simulations, we find that the gliding dislocations experience significant hardening due to pinning and depinning caused by random compositional fluctuations, with higher SRO decreasing the degree of USFE dispersion and hence, amount of hardening. Finally, we show how the morphology of an expanding dislocation loop is affected by the applied stress, with higher SRO requiring higher applied stresses to achieve smooth screw dislocation glide. |
Proceedings Inclusion? |
Planned: |
Keywords |
High-Entropy Alloys, Computational Materials Science & Engineering, Machine Learning |