Study on minimum quantity lubrication in micro-grinding

This paper discusses the performance of the minimum quantity lubrication (MQL) in micro-grinding based on ground surface roughness and tool life. The effects of grinding and lubricating parameters on machining performance are studied. Experiments for dry grinding and grinding with pure air are also conducted for comparison. It is observed that surface roughness and tool life are improved with the application of MQL in micro-grinding. Experimental results show that efficient chip removal from the cutting zone in micro-grinding is important for achieving good surface finish and adequate tool life. The application of a small amount of cutting oil in MQL can significantly extend the tool life. In this study, the tool life in MQL is seven times longer than that in dry grinding and five times longer than that in grinding with air cooling. If the oil flow is surplus to requirements or the air flow is inadequate, excess oil will stay on the grinding tool after the grinding test. As a result, poor surface roughness is observed. The optimal lubrication conditions in this experimental exploration are the combination of an oil flow of 1.88?ml/h and an air flow of 25?L/min.