双锋角钻头钻削碳纤维增强树脂基复合材料钻孔缺陷的研究

Defects in Drilling Carbon Fiber Reinforced Plastics with Double Cone Drill

针对碳纤维复合材料钻孔时易产生撕裂、毛刺等缺陷的特点,采用双锋角钻头为研究对象,从横刃、第一主切削刃和第二主切削刃对孔入、出口缺陷的影响和加工参数对撕裂因子的影响规律等方面分析双锋角钻头钻孔特点,并与普通麻花钻进行对比。结果表明:在相同的加工参数下,双锋角钻头双主切削刃加工特点降低了入、出口钻削轴向力,有效抑制了入、出口撕裂、毛刺等缺陷产生,更适合于钻削碳纤维复合材料。主轴转速增大有利于减小撕裂因子,随着进给速度的增加撕裂因子呈增大的趋势。采用多元线性回归方法建立了试验两种钻头钻孔入、出口的撕裂因子与加工参数之间的回归预测模型。

Defects such as burrs and tear,often occur in the drilling of CFRP. Drilling characteristics of double cone drill was studied through analyzing the influence of chisel edge and primary drilling edge and secondary drilling edge on defects of hole＇s entrance and exit and the influence regularity of processing parameters on tear factor. The results were compared with those of twist drill. Results show that,compared with twist drill,double cone drill is more suitable for drilling CFRP. The characteristics of double main cutting edge reduced the drilling axial force at hole＇s entrance and exit,inhibited burrs and tear damages at hole＇s entrance and exit. High speed drilling is favorable for minimizing the tear factor,the tear factor increases with the feed rate increasing. Through multi-linear regression analysis method,the prediction model between tear factor which is used to test hole＇s entrance and exit of the two drill and process parameters were established.