Crystals deformation structures named mechanical twins. The material is a mixture of titanium and aluminium which lead to a particular crystal structure. At room temperature, this material deforms by mechanical twinning located in very fine bands forming this particular structure.
This image show a composition of the material microstructure measured by electron backscattered diffraction and the surface strain field measured by digital image correlation after deforming the specimen by 0.2%. All measurements were done in a scanning electron microscope. The electron diffraction was measured with a spatial resolution of 1 micron whereas the deformation structures obtained with one tenth of a micron.