Influences of milling strategies and process parameters on the cavity defect generated during milling of carbon fiber reinforced polymer

Abstract

The burrs and delamination induced in milling of carbon fiber reinforced polymer have been studied extensively to suppress them. The cavity defect is still generated frequently on the machined surface of carbon fiber reinforced polymer when the fiber cutting angle is obtuse, resulting in the performance degradation of carbon fiber reinforced polymer parts. Nevertheless, there are a few researches on the cavity defect and the effectiveness of the evaluation methods for characterizing the cavity defect is not clearly given during milling of carbon fiber reinforced polymer. In this work, the objective is to obtain the nine combinations of milling strategy and process parameters to reduce the cavity defect in milling of carbon fiber reinforced polymer by multi-tooth tool. Two assessment methods of the cavity defect are proposed to quantitatively evaluate the cavity defect, including the average depth and volume of the cavities. Then, the influences of milling strategies and process parameters on the cavity defect are figured out, and the effectiveness of the assessment methods is analyzed. It is found that the average volume of the cavity is more proper to evaluate the cavity defect. The results indicate that the optimal combination of milling strategy and process parameters for low cavity defect and high material removal rate is up milling, low cutting speed, and high feed per tooth. The findings in this work could guide the high-performing milling of carbon fiber reinforced polymer parts with higher machining efficiency.