Abstract: Machining damages are easily to be generated during traditional drilling of carbon/epoxy (C/E) composites. Orbital drilling, as a new processing method, is increasing attractive during machining of aerospace materials. In order to investigate of mechanism of reduction of damage during orbital drilling, both orbital drilling and traditional drilling (as a comparison) are used to drilling of C/E composites, and the motion track of cutting tool of both orbital drilling and traditional drilling is studied. Based on the same machining efficiency and tool cutting speed, the machining parameters of the two methods are selected. Drilling experiment is carried out, cutting temperature, cutting force and machining quality are detected and analyzed. The results show cutting temperature has a great influence on the machining quality during drilling of C/E composites. And due to the cutting temperature during orbital drilling is much lower than that during traditional drilling, the machining quality of orbital drilling is much better than traditional drilling. Comparing with traditional drilling, the cutting temperature of orbital drilling decreases by 69 ℃, which is more than 36 %. Therefore, delamination and spalling are effectively avoided at exit.

Key words: C/E composites, Damages, Orbital drilling, Temperature, Traditional drilling