Experimental study and simulation analysis of the fracture mechanism in AFRP milling

The finite element model of aramid fiber reinforced polymer (AFRP) was established using the finite element analysis software, and milling simulation analysis was carried out. The influence of cutting speed and tool diameter on cutting force was obtained. Based on the motion law of the milling cutter, a fiber cutting mechanical model was established, and the influence of shear force and transverse pressure on the quality of the fiber section was analyzed. The milling experiment on AFRP specimens was carried out, and the milling appearance and cutting force variation of cutting speeds at 18.850–31.415 m/min and tool diameters of 1 –5 mm were studied. The results show that the diameter of a 5 mm milling cutter has a neater cutting fiber section and fewer burrs than the diameter of a 1 mm milling cutter, but inadequate sharpness can easily cause serious entrance burrs. Due to the influence of the feed motion, the milling tool feeding direction (X direction) is 42.456% higher than the Y direction cutting force, which can easily cause tool fracture. Increasing cutting speed can reduce cutting force to a certain extent and improve cutting quality. Therefore, choosing a large-diameter milling cutter with a large rake angle or relief angle for high-speed cutting can effectively improve the quality of the AFRP milling entrance and section.