Shape evolution and characteristics of carbon fiber reinforced polymer surface in laser ablation

Carbon fiber reinforced polymer (CFRP) has been far-ranging used for structural components in structural engineering. Laser paint removal is promising in the repair and maintenance of CFRP structural components. However, there are still many unknowns relating to laser paint removal, and the existing theory and practice are insufficient to guide the industrial application of laser paint removal from CFRP laminate. This paper uses nanosecond laser cleaning experiments on the paint of CFRP laminate surface to study the cleaning mechanism and cleaning effect of different process parameters for removing the paint. The surface morphology and three-dimension morphology of laser-cleaned samples are observed to reveal the cleaning quality. In addition, after laser paint removal, the nanostructures are generated on the carbon fibers (CFs) surface. The thermodynamic behavior of CFRP laminate during laser paint removal is discussed by the combination of experimental results and theoretical analysis. The contact angle measurements and single lap joints experiments demonstrate laser-cleaned surfaces present better wettability and higher tensile shear strength than other cleaning methods. This study provides a theoretical and experimental basis for the application of laser paint removal from CFRP laminate.