Thermo-mechanical coupled simulation of temperature distribution and material removal mechanisms in UD-CFRP orthogonal cutting

Abstract

Carbon fibre reinforced plastics (CFRPs) tend to generate high cutting temperatures during machining, which can exacerbate machining-induced damage. Although previous studies have examined CFRP cutting behaviour under thermo-mechanical coupling, the influence of cutting temperature on the mechanical properties of CFRP has rarely been considered. To address this issue, a thermo-mechanical coupled numerical model was established in this study to examine the material removal process. Within this model, the degradation equations of the mechanical properties with temperature variation were fitted. Based on this model, chip formation, cutting force, and cutting temperature were predicted at fibre cutting angles (FCAs) of 0°, 45°, 90°, and 135°, and the predictions were validated experimentally. The results indicate that the maximum prediction errors for cutting force and cutting temperature are 14.1% (at 90°) and 11.26% (at 135°), respectively. With increasing FCA, both cutting force and cutting temperature increase at first and then decrease. The influence of cutting temperature on subsurface damage depends strongly on the FCA. At 0° and 45°, the thermal effect on subsurface damage is relatively limited. In contrast, at 90° and 135°, increased temperature promotes subsurface crack propagation, resulting in subsurface damage depths of 217.08 μm and 122.65 μm, respectively.