Dimethicone-assisted interlaced scanning compound cutting for regulating thermal damage in CFRP laser cutting by synergistic suppression of coupled heat effect

Abstract

Carbon fiber reinforced polymer (CFRP) is prone to produce significant thermal damage such as heat-affected zone (HAZ) during laser cutting, which seriously affects the processing quality. In this paper, a new method of dimethicone-assisted interlaced scanning mode (DISM) compound cutting is proposed to regulate the surface damage of CFRP nanosecond UV laser hole cutting. Based on the simulation and experimental testing analysis, the coupling effect of heat conduction and heat accumulation during the laser cutting process, as well as the suppression mechanism of heat effects by compound cutting methods have been described. Compared to the default cutting method, DISM can effectively reduce the damage of CFRP laser hole cutting. The average matrix recession (MR) width of the hole entrance edge is reduced by 47.54% for DISM, while eliminating the heat-damaged matrix (HDM) zone, resulting in a comprehensive reduction of HAZ by 85.2%. The most obvious parameter combination for the reduction of MR width is 50 kHz, 1000 mm/s, and 0.06 mm, where the MR is reduced by 61.31% (37.61 μm→14.55 μm). Interlaced scanning mainly reduces MR width, while dimethicone-assisted processing exhibits suppression of HDM. The compound cutting method significantly reduces thermal damage and improves CFRP mechanical properties.