About this Abstract |
Meeting |
2021 TMS Annual Meeting & Exhibition
|
Symposium
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Heterostructured and Gradient Materials (HGM IV): Tailoring Heterogeneity for Superior Properties
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Presentation Title |
Shape Memory Alloys: Using Heterostructure-induced Defects to Train Thermo-mechanical Response |
Author(s) |
Peter Martin Anderson, Harshad Paranjape, Sivom Manchiraju, Michael Mills |
On-Site Speaker (Planned) |
Peter Martin Anderson |
Abstract Scope |
Shape memory alloys rely on tuning of lattice parameters and nucleation/pinning sites to finesse desired properties. Austenite-martensite interfaces can move at substantial fractions of the speed of sound and inject remnant dislocation structure and residual stress that “train” the material. The stress-induced transformation can be "tamed" from a sharp, abrupt process to a smoother, more continuous, reversible one that evolves over a range of stress. These phenomena are studied using a relatively new phase field-finite element formulation that captures the dynamics of the phase transformation. The results show that moving austenite-martensite interfaces can literally "write-in" specific dislocation slip patterns that are signatures of the particular interface and its velocity. A comparison with high resolution TEM micrographs highlights the competition between transformation and plasticity at interfaces and its regulation by stress gradients. |
Proceedings Inclusion? |
Planned: |