Martensitic Transformation in Crystal-Amorphous Superlattices of NiTi Shape Memory Alloy
Bhavna Singh, Shivam Tripathi · arXiv · 2026
Crystal-amorphous superlattices in NiTi are simulated to shift martensitic transformation behavior, boosting reversibility and stiffness while raising transformation critical stress.
Plain English summary
Why this matters
Key findings
- Partial amorphization modifies the martensitic transformation pathway, adding an initial continuous (second-order-like) transformation before the conventional first-order step.
- Thermal hysteresis decreases from 275 K (fully crystalline NiTi) to 95–110 K (CAS-NiTi).
- Elastic modulus increases by ~60–90% depending on crystalline fraction.
- Critical stress for stress-induced martensitic transformation increases by ~60–90% depending on crystalline fraction.
- Mechanisms attributed include heterogeneous nucleation at crystal-amorphous interfaces, retained austenite aiding reverse transformation, and mechanical constraint from the amorphous phase.
Limitations
The abstract reports results from large-scale molecular dynamics simulations; it does not provide experimental validation, and it does not specify which specific crystalline/amorphous architectures beyond “different crystalline phase fractions” were studied.
Publication
- Publisher
- arXiv
- Publication date
- July 3, 2026
- Research type
- Preprint
- arXiv
- 2607.03172
- Access
- open
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