C/E复合材料螺旋铣削制孔方法抑制缺陷产生的机理

Mechanism of Reduction of Damage during Orbital Drilling of C/E Composites

传统钻削加工碳纤维/环氧树脂(Carbon/epoxy,C/E)复合材料时容易产生加工缺陷,而螺旋铣削作为一种新的制孔方法在航空材料的加工中逐渐受到关注。为分析螺旋铣削制孔方法抑制缺陷产生的机理,以传统钻削加工为参照,分别利用螺旋铣削及传统钻削两种方法对C/E复合材料进行制孔试验,并对螺旋铣削与传统钻削刀具的运动轨迹进行分析。在具有相同的加工效率及刀具切削速度的基础上,对两种加工方法的加工参数进行优化。进行制孔对比试验,并对制孔过程中的切削温度、切削力及加工质量进行检测与分析。结果表明,切削温度是影响C/E复合材料制孔质量的重要因素,且由于螺旋铣削制孔时的切削温度显著低于传统钻削制孔温度,因此螺旋铣削制孔质量明显优于传统钻削制孔质量。螺旋铣削制孔时的切削温度较传统钻削时降低69℃以上,降幅大于36%,因此有效避免了制孔出口处的撕裂及分层现象。

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.