Experimental study on wear laws and mechanisms of end cutting edge in end-milling of carbon fiber reinforced polymer

End cutting edges of tool determine machining quality of the bottom surface of the slot in end-milling of CFRP. However, due to anisotropy and heterogeneous of CFRP, and also semi-closed characteristic of blind slots, the end cutting edges are more vulnerable to wear than the peripheral edges under the strong abrasive fibers, leading to the poor machining quality of the bottom surface of the slots, and thereby decreases the assembly performance of the components. This paper aims to reveal the wear laws and mechanisms of the end cutting edge which serves under the poor machining conditions in end-milling of CFRP. In order to obtain major wear forms of the end cutting edge, the tool's structure and the removal characteristics in end-milling of CFRP are analyzed. For acquiring the wear laws accurately, slot-milling experiments are conducted, in which the quantitative characterization of each wear form is proposed. According to the wear laws obtained from the experiments, combining with the associated relationships of each wear form, the wear mechanisms of end cutting edge are revealed, and also, the influences of the tool wear on the surface's machining quality are got. The results show that there are three wear forms in all including the corner wear, the cutting-edge wear, and the flank wear. Concretely, the corner wear is rapid; the cutting-edge radius is fluctuating and tends to decrease, while the flank face is wearing constantly. The conclusions of this study can provide foundations for further studies on suppression of the tool wear.