Micro-liter lubrication machining of Inconel 718

Minimum quantity lubrication (MQL) machining is one of the promising solutions to the requirement for decrease in cutting fluid consumption. This paper describes MQL machining in a range of oil consumption <1.0 ml/h, which is 10–100 times smaller than the consumption usually adopted in industries. MQL machining in this range is called micro-liter lubrication machining in this paper. A specially designed nozzle was used for concentrating small amounts of oil mist onto the cutting interface. The performance of concentrated spraying of oil mist in micro-liter lubrication machining of Inconel 718 was investigated and compared with that of ordinary spraying. This proved that the concentrated spraying of oil mist with a specially designed nozzle was quite effective in increasing tool life in the micro-liter lubrication range.