Although laser shock peening (LSP) was applied in metals for property enhancement for a long time, its application on brittle materials has not been investigated so far. The present work was the first computational attempt to show that strong dislocation activity could be generated in Si crystal by a modified LSP process. Multi-scale dislocation dynamics plasticity (MDDP) simulations were conducted to predict the dislocation structure and stress/strain distribution in Si crystal during LSP. In the modified LSP process, dislocation mobility of Si and shock pressure was sufficiently high to generate and transport dislocation. The relationships between dislocation activities, the laser processing conditions and ablative coating material were systematically investigated. It was found that dislocation density, dislocation multiplication rate, and dislocation microstructure strongly depend on LSP processing conditions. This LSP process could also be applied in other brittle materials.

Multiscale Dislocation Dynamics Analyses of Laser Shock Peening in Silicon Single Crystals. G.J.Cheng, M.A.Shehadeh: International Journal of Plasticity, 2006, 22[12], 2171-94