通过钛合金TC4的铣削实验,研究冷风油雾润滑介质特性及其施加方式对刀具-切屑摩擦行为的影响。冷风油雾喷嘴布置在刀具将要切入工件前的空行程中,其润滑效果最好。当出油量增加到一定值(约12 mL·h-1)时,刀具-切屑平均摩擦系数不再发生明显变化。随着钛合金TC4铣削速度的提高,冷风干切削的平均摩擦系数增大,而冷风油雾切削的平均摩擦系数变化不明显,且远低于冷风干切削的平均摩擦系数。结果表明:油雾载体速度和刀具转速存在一定的匹配关系,使润滑效果达到最优。
Milling experiments of titanium alloy TC4 with cold air oil mist lubricant have been performed.The effect of the lubricant properties and its applying way on friction behavior between the cutting tool and the chip has been studied. The optimal lubrication effect takes place when the cold air oil mist nozzle is set in the idle stroke before cut-in process. When the spray quantity is up to some value (about 12 mL·h-1 in this study),the average friction coefficient between cutting tool and chip has no obvious change.Average friction coefficient increases with the increasing milling speed of the titanium alloy TC4 in the cold air dry cutting,while the average friction coefficient does not change obviously in the cold air oil mist cutting,and it is far lower than the average friction coefficient in the cold air dry cutting.The results show that there is a certain relationship between the spray speed and the milling speed,which makes an optimal lubrication.