Delamination in titanium-based carbon-fibre/epoxy laminates under laser shock peening

Abstract

Surface modification of titanium-based carbon-fibre/epoxy laminates (Ti-CF FMLs) is a challenging topic due to its multilayer structure. This paper investigates the delamination behavior of the Ti-CF FMLs under laser shock peening (LSP) based on experimental and numerical methods. The results show that the onset of the delamination of the Ti-CF FMLs depends on LSP treated area and the delamination width along the thickness direction increases with LSP area. The direct effect of LSP is to degrade the scalar stiffness of the interface between metal and CFRP layers in the Ti-CF FMLs instead of inducing delamination. As massive LSP are performed, the compressive residual stress produces reverse bending, thus delamination occurs at the damaged interface. The damage of the adhesive layer can be effectively prevented by reducing the laser spot size.