Chip Formation Mechanism of Deep?Hole Gun Drilling of Ti6Al4V Titanium Alloy

Ti6Al4V钛合金深孔枪钻加工切屑成形机理

During the process of deep?hole gun drilling,the shape of the chip is a significant factor affecting the final quality.The relationship between chip forming mechanism and process parameters has always been a complicated problem in deep?hole drilling.This paper investigates Ti6Al4V titanium alloy to address this issue.First,the four processes and influencing factors of forming spiral chips are analyzed theoretically.Second,the fracture mechanism of chips in drilling Ti6Al4V titanium alloy is analyzed by scanning electron microscopy.Finally,the influences of cutting speed,feed rate and coolant oil pressure on chip shape are analyzed through drilling experiments and fluid simulation.The relationship between chip compression ratio and surface roughness is obtained through chip thickness measurement.This research can provide a guide for optimizing parameters of deep?hole gun drilling on Ti6Al4V titanium alloy.

深孔枪钻加工过程中,切屑形貌是影响其加工质量的一个重要因素,并且切屑的成形机理与工艺参数之间的关系也一直是深孔加工研究的难点。本文以Ti6Al4V钛合金为研究对象,一方面,通过理论分析了枪钻加工螺旋形切屑成形的4个过程和影响因素;另一方面,借助于扫描电镜检测研究了Ti6Al4V钛合金枪钻加工切屑的断裂机理;最后,通过加工试验和流场仿真,分析了切削速度、进给量和冷却液油压变化对切屑形貌的影响,结合切屑厚度测量得出了切屑压缩比与表面粗糙度的关系。研究结论对Ti6Al4V钛合金深孔枪钻加工工艺参数的优化提供了指导。