Evaluation of shock-wave-induced plastic deformation of silicon single crystal using time-resolved Laue diffraction

The generation of dislocations under shock compression is a fundamental phenomenon of critical importance for understanding the initial stages of plastic deformation and subsequent fracture in solids. In this study, we focus on the shock-wave-induced plastic deformation of silicon single crystals. Anisotropic compression behavior was observed for the diffraction spots −3 1 1 and 3 1 1, which are sensitive to the strain along the shock wave propagation direction 001, using time-resolved Laue diffraction, suggesting that elastic deformation had reached the elastic limit. The diffraction spots −2 −2 0 and 2 −2 0, which are sensitive to shear deformation perpendicular to the 001 direction, were separately observed under laser-induced shock compression, and their broadening owing to the increasing mosaicity was analyzed. At the elastic limit, the crystal lattice angle changes owing to stacking faults caused by partial dislocation generation, and the transient dislocation density under shock compression can be derived from the tilt angle of separated diffraction spots. A broadened peak corresponding to Δθ = 8.3° ± 2 was observed on the high-angle sides of −2 −2 0 and 2 −2 0, leading to an estimated transient dislocation density of 1.4 ± 0.6 × 1013 cm−2. This result provides insights into the generation and growth of transient partial dislocation densities in single crystals under shock compression.