Plastic Deformation in Silicon Crystal Induced by Heat-Assisted Laser Shock Peening

Abstract

The response of solid to shock compression has been an interesting topic for more than a century. The present work is the first attempt to experimentally show that plastic deformation can be generated in brittle materials by a heat-assisted laser shock peening process, using silicon crystal as a sample material. Strong dislocation activity and large compressive residual stress are induced by this process. The dislocation structure is characterized with transmission electron microscopy and electron backscattered diffraction. The residual stress is measured using Raman scattering. This work presents a fundamental base for the application of laser shock peening in brittle materials to generate large compressive residual stress and plastic deformation for better mechanical properties, such as fatigue life and fracture toughness.