Experimental study on the sidewall quality of femtosecond laser drilling CFRP

Abstract

This study investigated the effect of laser angle-of-incidence (AOI) on the sidewall quality of femtosecond laser drilling carbon fiber-reinforced plastic (CFRP). The results indicated that increasing the laser AOI could prevent laser blockage by the sidewall, reducing fiber loss and resin melting and re-solidification. The laser energy density was also raised with a larger laser AOI, which enhanced the laser processing efficiency and reduced the sidewall taper. However, this also led to cavities and crevices caused by the resin loss between the fibers. By adjusting the drilling strategy and the laser energy, the sidewall taper was eliminated, and the resin loss was reduced. This work proposes a novel approach to enhance the sidewall quality of femtosecond laser drilling CFRP, which has implications for the manufacturing and application of CFRP components.