Research on three-dimensional cutting force theoretical model of turning glass-ceramics based on discretization of cutting edge

Cutting force is one of the most important physical quantities in the cutting process. Cutting force directly determines the generation of cutting heat and affects tool wear and machined surface quality. In this work, based on the geometric analysis of the turning tool, the cutting edge was discretized, and the local parameters of each cutting edge were calculated. According to the formation and assumption of brittle material chips, considering the energy dissipation in the process of chip formation, the cutting force of each cutting edge element was calculated. Then, the theoretical model of three-dimensional turning force of glass-ceramics was established by adding the forces contributed by all cutting edge elements. The change of tool geometry angle can lead to the change of local cutting parameters at each point on the cutting edge, thereby affecting the variation of cutting force. In order to evaluate the cutting force model, the turning experiment of fluormica glass-ceramics was carried out, and the influence of tool geometry angles (normal rake angle gamma n, tool nose radius r epsilon, and tool cutting edge angle kappa r) on the cutting force was discussed. The predicted results are in good agreement with the measured results. This model can provide theoretical guidance for the efficient turning strategy of glass-ceramics.