A mechanistic model for cutting force in helical milling of carbon fiber-reinforced polymers

Recently, carbon fiber-reinforced polymers (CFRPs) are widely used in the transportation, aerospace, and chemical industries. In order to complete reliable connection with other materials, hole-making performance about CFRP must be systematically studied. While as the typical difficult-to-cut material, tool wear will be very serious in the CFRP cutting process, which will directly influence the change of cutting force, and the larger of the cutting force will lead to the occurrence and propagation of delamination of the holes. In this paper, to accurately predict cutting forces in helical milling of CFRP, a mechanistic cutting forces model considering the fiber cutting angle is established according to cutting principle of helical milling. Based on experimental data, cutting force coefficients are identified according to unidirectional CFRP using average-based method and fitted by response surface methodology (RSM). The results show that the new established force model with the cutting force coefficients can improve the accuracy of the cutting forces, thus achieving an accurate estimate of cutting forces in helical milling of carbon fiber-reinforced polymers.