A Review on Minimum Quantity Lubrication (MQL) for Sustainable Machining Processes and its Application

The use of cutting fluid by industrial manufacturers has benefited the machining processes, effectively. Cutting fluids reduce the temperature of the surface, frictional effects; it also removes chips by flushing them and therefore extends tool lifespan by improving machining performance. However, the consumption of excess amount of cutting liquid arises concern in regard to production rate and ecological problem. Therefore, a common target of manufactures is to develop a safer working atmosphere and reduce production cost by drastically reducing the use of cutting fluid in machining. The feasible solution to achieve this goal is minimum quantity lubrication (MQL), in which we deliver the lubricant at very small flow rate to machining zone. MQL technique has evidence, as it is suitable to comply for the fulfillment of ‘Green Machining'. Therefore, in this study, the effects of MQL in turning, drilling, grinding and milling application using mineral oils (base oils), vegetable oils (synthetic oils), and Nano-fluids on various materials are discussed.