Synergistic effect of a nanosecond-picosecond combined pulse laser on the regulation of surface properties and interfacial bonding strength of CFRP

Surface treatment of carbon fiber-reinforced polymer (CFRP) is a critical step in industrial processing. This study introduces a surface treatment method for CFRP using an infrared nanosecond-ultraviolet picosecond combined pulse laser. By adjusting the power ratio of the combined laser, we analyzed changes in surface morphology, roughness, wettability, and interfacial bonding strength. The optimal processing parameters were identified, and the synergistic mechanism of the dual-pulse-width, dual-wavelength laser was elucidated. Experimental results indicate that the combined pulse laser effectively removes resin from the CFRP surface, significantly increasing surface roughness. Surface free energy improved by 41.6%, and interfacial bonding strength increased by 40.6% compared to untreated surfaces.