Ti6Al4V Titanium Alloy with Gundrill

Abstract:In deep hole gun drilling，cutting fluid plays a role of lubrication，chip removal and cooling，the coolant pressure is one of the important factors that affect the processing quality.In this paper，based on the computational fluid dynamics(CFD) theory，the coolant pressure is used as a single factor variable to simulate the flow field of 17mm standard gun drill，and combined with the experiment to discuss the oil pressure on chip breaking，chip removal and drilling stability influences.The results show that the energy transfer between the fluid and solid in the flow field is mainly concentrated at the outlet of the bottom clearance and near the cutting edge，and the transfer capacity increases with the increase of coolant pressure.Therefore，when the coolant pressure is too small，it is easy to cause chip blocking and worsen the machining quality；when the pressure is too large，the chip is short and easy to discharge，but the drilling stability is poor，which leads to the decline of machining quality.It is recommended that the coolant pressure of 17mm gundrill should be 4MPa when processing Ti6Al4V titanium alloy.