Effect of laser cleaning on adhesive properties of carbon fiber composite materials

Abstract

A pulsed fiber laser was used to conduct laser cleaning experiments on the composite paint layer on the surface of carbon fiber composite materials (carbon fiber-reinforced plastic (CFRP)). The influence of laser energy density and laser travel speed on the cleaning effect was studied. The surface morphology, surface roughness and phase composition of the cleaned sample were analyzed. After bonding, tensile testing was conducted on the bonding part to verify the impact of laser cleaning on the bonding performance. The research results indicate that the cleaning effect gradually improves with the increase of laser energy density or the decrease of travel speed. In this experiment, when the laser energy density is 4.00[Formula: see text]J/cm2 and the travel speed is 6.5[Formula: see text]mm/s, the phase composition of the cleaned substrate surface is only C, without TiO2 and BaSO4. This indicates that the paint layer has been completely removed under this process parameter. By selecting reasonable process parameters, the surface paint layer of CFRP can be effectively removed, and a good surface morphology can be obtained without damage to the carbon fiber. Meanwhile, the mechanical properties after bonding can be improved.