Brittle fracture studied by ultra-high-speed synchrotron X-ray diffraction imaging.

investigations of cracks propagating at up to 2.5 km s along an (001) plane of a silicon single crystal are reported, using X-ray diffraction megahertz imaging with intense and time-structured synchrotron radiation. The studied system is based on the Smart Cut process, where a buried layer in a material (typically Si) is weakened by microcracks and then used to drive a macroscopic crack (10 m) in a plane parallel to the surface with minimal deviation (10 m).