Three-dimensional subtractive manufacturing of CFRP using water jet-guided laser processing: achieving low thermal damage and thin recast layers

With the global rise of the low-altitude economy, carbon fiber-reinforced polymers (CFRPs) are playing an increasingly important role in the lightweight design of drones and electric vertical take-off and landing vehicles. However, conventional processing techniques, including mechanical machining and conventional laser processing, often fail to prevent the formation of microscopic defects such as fiber tearing, delamination, and burr formation during the fabrication process. Additionally, the heat accumulation inherent in laser cutting can cause thermal damage to the edges and cross-sections, significantly compromising the mechanical integrity and brittle characteristics of CFRP materials. In this study, we propose a low-thermal-impact processing strategy based on water jet-guided laser (WJGL) technology for rapid subtractive manufacturing of CFRP. Compared with the traditional focused nanosecond pulse laser method, WJGL effectively suppresses heat accumulation, without a heat-affected zone (HAZ), and controls the slit width error below 3%, allowing the processed workpieces to be tightly combined and achieving precision machining. This approach facilitates one-step processing and molding of large-area CFRP substrates with complex three-dimensional geometries and fine spatial structures, showing its broad prospects as a future multi-task micro-machining center.