Abstract Scope |
Martensitic phase transformation is the enabling deformation mechanism behind a diversity of materials including multiferroics, shape memory alloys, and lightweight steels. Martensitic phase transformation operates via phase interfaces that mobilize across the microstructure, often while generating defects. Under certain conditions, the transformation is reversible, making it observable only through in-situ characterization. Here, we use synchrotron X-ray characterization to resolve the hierarchical nature of martensitic phase transformation micromechanics in situ, in 3D, and across length scales. We present experimental results on the evolution of martensite morphology, interfacial stress fields at the austenite-martensite interface, and how martensitic phase transformation interacts with and generates defects during stress-induced martensitic phase transformations in CuAlNi shape memory alloys using X-ray topotomography, diffraction contrast tomography, and dark-field X-ray microscopy. The results demonstrate how recent and ongoing advances in synchrotron X-ray characterization techniques can be used to shed new light on complex, metastable micromechanical behaviors. |