Micro-Scale Orthogonal Cutting of CFRP/AFRP Laminates: Modeling and Experimental Analysis

With the ongoing advancement of composite materials, CFRP/AFRP laminates, which integrate the benefits of carbon fiber-reinforced polymer (CFRP) and aramid fiber-reinforced polymer (AFRP), have become increasingly utilized in aerospace applications. The distinct material properties of carbon fibers and aramid fibers result in differing fracture and damage mechanisms during machining. Thus, understanding the cutting and damage mechanisms of CFRP/AFRP composites is crucial to achieving high-quality machined surfaces. In this study, a micro-scale orthogonal cutting finite element model (FEM) is developed for CFRP/AFRP laminates, and corresponding orthogonal cutting experiments are conducted. The cutting process and damage formation mechanisms are analyzed for four typical fiber cutting angles from a microscopic perspective. The findings reveal that carbon fibers, due to their brittleness, primarily undergo shear and bending fractures, while aramid fibers, exhibiting higher ductility, predominantly experience shear and tensile fractures. The surface quality of CFRP/AFRP laminates declines as the fiber cutting angle increases. The cutting force initially rises and then declines as the fiber angle increases, peaking at a 90° fiber cutting angle. The simulated cutting process and cutting forces correspond well with experimental results. Additionally, subsurface damage is assessed, showing that it increases with cutting depth and decreases with cutting speed, stabilizing at higher cutting speeds.