A comparative experimental study of unidirectional CFRP high-speed milling in up and down milling with varied angles

Precision machining of Carbon Fiber Reinforced Polymer (CFRP) is challenging due to its high strength and anisotropic microstructure. This study proposes a specially designed cutting experiment method to understand the influence mechanism of cutting force and surface quality in CFRP high-speed cutting process. The study examines the influence of fiber cutting angle, up/down milling, and machining parameters on the side milling of regular 12-corner unidirectional CFRP samples. Cutting force and surface quality are evaluated to analyze the machining process. The results show that the cutting angle is a key factor influencing milling force and surface quality. For cutting along the fiber, force follows 60 & DEG; > 30 & DEG; > 90 & DEG; > 0 & DEG;, and against the fiber, it follows 90 & DEG; > 180 & DEG; > 150 & DEG; > 120 & DEG;. The 90 & DEG; cutting angle provides optimal surface quality, and cutting against the fiber fa-cilitates material removal. Up-milling can reduce cutting force by 15 %-20 % and surface roughness Sa by up to 25 % compared to down-milling, while improving tool durability. High-speed cutting can reduce surface roughness by at least 35 %. These findings can optimize CFRP machining processes and improve quality results.