High-resolution deformation mapping of martensitic transformation and plasticity in superelastic Nickel-Titanium

Shape-memory alloys (SMAs) such as nitinol (NiTi) can recover large strains through a reversible stress- or temperature-induced martensitic transformation, but cyclic transformation degrades reversibility. Recent experimental evidence has linked this functional fatigue to the emission of dislocations from the fine martensitic microstructure that forms near the phase boundary, but the precise coupling mechanism between dislocation slip and martensitic microstructure is still widely debated. This creates a mesoscale gap in the understanding of SMAs and their fatigue: multiscale simulation is prohibitively expensive, while experimental methods that can spatially resolve fine microstructure and individual dislocations (e.g., transmission electron microscopy) cannot capture bulk mechanical behavior. In biomedical applications, understanding and modeling the mechanisms of slip localization and functional fatigue will be particularly crucial for the newest generations of ultra-high-purity niti..., , # High-resolution deformation mapping of martensitic transformation and plasticity in superelastic Nickel-Titanium

Dataset DOI: [10.5061/dryad.xsj3tx9tn](https://doi.org/10.5061/dryad.xsj3tx9tn)

## Dataset overview

This study investigated the interactions between martensitic phase transformation and plastic slip in superelastic Nickel-Titanium (NiTi, or nitinol). The experiment was designed to be analogous to the early-stage duty cycle of a nitinol cardiovascular implant. The dataset comprises the following:

1. **SEM-DIC (HR-DIC)**: high-resolution, sub-grain deformation maps obtained via in situ scanning electron microscopy digital image correlation (SEM-DIC, sometimes called HR-DIC)
2. **EBSD**: orientation maps obtained via electron backscatter diffraction (EBSD)
3. **MMICROSTRUCTURE**: activity fields for each slip system and martensitic variant reconstructed via the MMICROSTRUCTURE framework, which is developed and presented in the accompanying publication

Full experimental de...,