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A numerical-analytical approach was utilized to construct a predictive model of cutting force for machining unidirectional carbon fiber reinforced polymer (UD-CFRP) laminates. The force coefficients in the model, which include friction angle, shear plane angle, shear strength, and rebound height, can be characterized by the fiber orientations ranging from 0° to 180°. The accuracy of the model was confirmed through experimental verification. The results indicate good agreement between the predicted and experimental values, with relative errors below 14.8%, except for the thrust force at 90°. Additionally, the study examined the influence of rake angle and flank angle on the cutting force, revealing two critical points in the predicted cutting force curve throughout the fiber orientation. These turning points shifted with changes in the rake angle. For instance, the value of the first critical point changes from 60° to 45° when the rake angle range shifts from [0°, 5°] to [10°, 15°]. This indicates that a larger rake angle facilitated an earlier transformation of chip formation mode, leading to a decrease in cutting force. Furthermore, the cutting force decreased as the rake angle increased between the two turning points. The impact of the flank angle on the cutting force was determined to be minimal, and the turning points' positions remained consistent as the flank angle increased. [ABSTRACT FROM AUTHOR]

A three‐dimensional (3D) microscopic finite element (FE) cutting model was developed with the thermo‐mechanical coupling for carbon fiber reinforced polymer (CFRP) composites in this article. The model predictions of cutting force, machined surface, and cutting temperature at various fiber orientations were obtained and compared with the experimental data. It was shown that the 3D microscopic cutting model can predict the cutting force, cutting temperature, and subsurface damage precisely. The behavior of cutting force has presented an obviously cyclical variation characteristics at the fiber orientations of 0°, 45°, and 90°, and different chip morphologies were obtained correspondingly. The temperature fields of machined surface were studied at the four different fiber orientations, in which the maximum residual temperature on the machined surface occurs at 90°. The heat‐induced resin coating and resin ridges on the machined surface were obviously observed at the fiber orientations of 45° and 135°. The trend curve of cutting temperature is more similar with that of thrust force by comparing with cutting force, which meaning, unlike the isotropic metal materials, the thrust force has the direct effect on the heat generation. In addition, the comparison of depth of thermal and mechanical subsurface damage was also performed, it was showed that the depths of thermal subsurface damage are close to that of mechanical subsurface damage in the range of 0°–45°, and the thermal subsurface damage decrease while the mechanical subsurface damage increases with the increase of the fiber orientation range from 90° to 180°. [ABSTRACT FROM AUTHOR]

A three-dimensional micromechanical finite element cutting model with the thermo-mechanical coupling was developed for carbon fiber reinforced polymer composites in the paper. The finite element modeling considers the three phases of a composite, in which the interphase between the fiber and matrix can realize heat transfer and allow debonding to represent the failure of composites. The model predictions of the machining responses, such as cutting temperature and subsurface damage, at different fiber orientations were compared with various experimental data for model validation. It is indicated that the three phase micromechanical model is capable of precisely predicting cutting temperature and the damage induced by the cutting tool. It was found that cutting temperature and subsurface damage strongly depend on the fiber orientation. Subsurface damage is easily occurs in a fiber orientation range of 90°–135°, while the largest depth of the thermal damage occurs at 90°. In addition, the effect of machining parameters on the cutting temperature was investigated based on the cutting model. It was showed that the cutting speed should be reasonably selected to control the cutting temperature. The temperature decrease with increase the rake angle, while increase with increase depth of cut and radius of cutting edge. [ABSTRACT FROM AUTHOR]

The paper aims to investigate the correlation of microstructural characteristics and machinability of unidirectional carbon fiber reinforced polymer composites by a modified analytical model. A representative volume element was selected to present the microstructure and analyze the force distribution, in which the interphase between the fiber and the matrix was considered significantly. And the microstructure can be obviously measured by using microscopic observation, especially the interphase was found to be around 0.3 μm in the used carbon fiber reinforced polymer composites. To study the representative volume element effect on the cutting behavior of unidirectional carbon fiber reinforced polymer composites, the prediction of cutting force was done by using a modified force model. Compared with the experiments, the developed model can well predict the cutting forces and subsurface damage in the carbon fiber reinforced polymer composites cutting. It was found that surface integrity as well as subsurface damage has a coincident varying trend with the fiber orientations, as confirmed by the observations of the machined surface at different fiber orientations. The good surface integrity can be obtained at the low fiber orientation of 0° and the poor surface occurs at the large fiber orientation of 135°. Moreover, the effect of interphase and the fiber volume fraction in representative volume element were further investigated. The results show that the cutting forces increase with increasing the fiber volume fraction as well as the interphase volume fraction, and the interphase affects the cutting force in the transverse direction is significantly higher than that in longitudinal direction. [ABSTRACT FROM AUTHOR]