About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
|
Computational Thermodynamics and Kinetics
|
Presentation Title |
A Novel Approach to Realizing Linear-Superleastic Behavior in NiTi SMA Using Precipitate Dissolution |
Author(s) |
Hariharan Sriram, Longsheng Feng, Yunzhi Wang |
On-Site Speaker (Planned) |
Hariharan Sriram |
Abstract Scope |
NiTi shape memory alloys (SMA) have various applications as cardio-vascular stents, actuators, and sensors. The shape memory effect is due to the reversible austenite to martensite transformation and the associated strain release. However, the large hysteresis (non-linear pseudoelasticity) observed in SMAs significantly impacts the efficiency and precision control. We propose a novel approach to tame martensitic transformation in NiTi by engineering concentration modulation (CM) in the parent austenite phase through the dissolution of Ni4Ti3 nanoprecipitates (observed in Ni-rich NiTi SMAs) to form a complex interpenetrating architecture with continuous variations in martensitic start temperatures. We show through Phase field simulations that the induced CMs in the parent phase effectively control the strain release by acting as nano-confinements to the martensitic transformation. A parametric study of the effect of the CMs wavelength and amplitude on the stress-strain behavior in NiTi SMAs will be presented. |
Proceedings Inclusion? |
Planned: |
Keywords |
Phase Transformations, Computational Materials Science & Engineering, Mechanical Properties |