Drilling trials were carried out on glass fiber reinforced plastics with twist drill which had S shaped drill tip coated by TIN and the ground surfaces of drilled holes were observed by using scanning electron microscope(SEM),the fracture mechanism of glass fiber and the microscopic characteristics of ground surfaces were analyzed.The experimental results show that twist drill with S shaped drill tip offers less drilling thrust force and delamination fracture campared with conventional twist drills.Therefore,

twist drill with S shaped drill tip is suitable for drilling glass fiber reinforced plastics and has a wide application prospect.

glass fiber reinforced plastic, S shaped drill tip, thrust force, delamination

选用S刃钻尖TIN涂层麻花钻对玻璃纤维增强复合材料进行了孔加工试验，并用扫描电子显微镜对孔壁表面进行了微观观察，分析了玻璃纤维破坏机理和切削表面微观结构特征。试验结果表明，S刃钻尖与普通钻尖麻花钻相比，可以有效减小钻削轴向力,减少分层缺陷的发生。因此，S刃钻尖麻花钻适用于玻璃纤维增强复合材料的加工，具有广泛的应用前景。

玻璃纤维增强复合材料, S刃钻尖, 轴向力, 分层