About this Abstract |
Meeting |
2025 TMS Annual Meeting & Exhibition
|
Symposium
|
Computational Thermodynamics and Kinetics
|
Presentation Title |
First-Principles Investigations of Martensitic Phase Transitions in NiTi-Based and Ru-based Shape Memory Alloys |
Author(s) |
Zhigang Wu, Hessam Malmir, John Lawson, Othmane Benefan |
On-Site Speaker (Planned) |
Zhigang Wu |
Abstract Scope |
Capability of accurately predicting phase transitions in shape memory alloys (SMAs) is crucial for developing novel SMAs with desirable properties, especially the high-temperature SMAs with martensitic transition temperatures (MTTs) well above room temperature. Here we present our first-principles investigations of Ni0.5Ti0.5-xHfx and PdxNi0.5-xTi0.5 ternaries, off-stoichiometric NixTi1.0-x, and RuNb. We show that the predicted phases and MTTs of all these SMAs are in good agreement (MTTs are within ~ 100 K) with the experimental data. Our results revealed the physical origin of the striking asymmetry in MTT of the off-stoichiometric NiTi near equi-atomic compositions and the transition paths and mechanisms of RuNb. We also found that the monoclinic phase of RuNb has the P2_1/m symmetry instead of previously identified P2/m. |
Proceedings Inclusion? |
Planned: |
Keywords |
Mechanical Properties, |