About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Computational Thermodynamics and Kinetics
|
| Presentation Title |
J-40: Regulating Stress-Strain Behavior of NiTi Shape Memory Alloys via 1D Nanoscale Concentration Modulations |
| Author(s) |
Zexu Chen, Hariharan Sriram, Longsheng Feng, Yunzhi Wang |
| On-Site Speaker (Planned) |
Zexu Chen |
| Abstract Scope |
NiTi SMAs are known for their large recoverable strains of up to ~10%. However, their non-linear pseudo-elasticity can lead to severe mechanical instability during application, characterized by strain plateaus and large stress-strain hystereses. Recent studies have shown that nanoscale concentration modulations (nanoCMs) in the B2 matrix of NiTi SMAs can effectively alter their stress-strain behavior due to the strong composition-dependence of the critical stress for stress-induced martensitic transformation. However, creating appropriate nanoCMs for desired mechanical responses remains a significant challenge. In this study, we demonstrate by using phase-field simulation how various 1D CMs of Ni with different wavelength, wave shape (trigonal, sinusoidal, etc.), amplitude and mean value affect the stress-strain behavior, including the size of hysteresis, the size of the strain avalanche, the overall linearity of the stress-strain curve, and the apparent elastic modulus. This research provides quantitative guidance for the design of nanoCM NiTi SMAs with novel mechanical properties. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, Modeling and Simulation, Mechanical Properties |