The feasibility of fast slotting thick CFRP laminate using fiber laser-CNC milling cooperative machining technique

Thermal damage is inevitable during laser cutting CFRP laminates due to significantly different thermal properties between carbon fiber and resin matrix, which severely affects the assembly accuracy and service performance of composite structures. This work proposed a newly designed fiber laser-CNC milling cooperative machining technique to slot 10.0 mm thick CFRP plates, it integrated the advantages of high efficiency and high material removal rate during high-power laser cutting process, together with good surface quality in milling with limited cutting allowance and high cutting speed. The influence of different machining strategy/method, cutting parameters and thermal damage on surface quality and morphology were comprehensively investigated. Thermal defects including cracks, striations, protruding fibers and matrix recession were the main damage during laser processing thick CFRP laminates, while laser-CNC milling cooperative machining technique successfully slotted 10.0 mm thick CFRP plate without thermal damage and kerf angle with the surface roughness (Sa) down to 5.4 mu m. Experimental results from this work indicated that the proposed cooperative machining technique was an alternative method for slotting thick CFRP laminates with superior quality and efficiency.