Investigation on laser paint stripping of CFRP: Morphological evolution, damage mechanism, and adhesive performance

Abstract

Damage to the substrate hinders the application of laser paint stripping (LPS) on carbon fiber reinforced polymers (CFRP), but the damage mechanism is currently unknown. In this paper, the LPS characteristics of CFRP, such as paint stripping depth, surface morphology and dynamic behavior, are firstly obtained. Subsequently, the surface damage mechanism of CFRP is discussed in detail by theoretical analysis and finite element method, and the effect of substrate damage on adhesive properties is investigated. The results show that it is difficult for LPS to obtain a complete surface free of paint residue. The strong laser plasma impact and resin pyrolysis pressure cause the resin to crack and flake before the paint is fully ablated. The carbon fiber then breaks and are thrown outward by heat and forces, and the surface with slightly fracture of the fiber will facilitate bonding with the paint.