Cooling and lubricating effects on tool wear and surface quality in ultra-precision machining

Abstract

To maintain tool sharpness or reduce tool wear and obtain better surface quality, the effects of dry cutting, minimum quantity lubrication (MQL), chilled air alone and chilled air with minimum quantity lubrication (CAMQL) on tool wear and surface quality are investigated in ultra-precision machining aluminium alloy and stainless steel that both have a strong affinity for diamond tool. The experimental results show that a proper employ of MQL and CAMQL would have much better effects than chilled air and dry cutting that lead to adhesion or tool wear; lubricating effect and cooling effect coexist and interact in MQL and CAMQL machining, they are influenced by the properties of different workpieces to some extent, i.e., lubricating effect is dominant while cooling effect is to sustain strength of the boundary film when ultra-precision machining aluminium alloy; cooling effect is dominant for reducing cutting temperature while lubricating effect is helpful to reduce abrasive wear when diamond turning plasma nitrided NAK80. These results are beneficial for various applications of MQL and CAMQL in ultra-precision machining.