The influence of minimum quantity of lubrication (MQL) on cutting temperature, chip and dimensional accuracy in turning AISI-1040 steel

In metal industries, the use of cutting fluid has become more problematic in terms of both employee health and environmental pollution. But the use of cutting fluid generally causes economy of tools and it becomes easier to keep tight tolerances and to maintain workpiece surface properties without damages. Because of them some alternatives has been sought to minimize or even avoid the use of cutting fluid in machining operations. Some of these alternatives are dry machining and machining with minimum quantity of lubrication (MQL). This paper deals with experimental investigations in the role of MQL on cutting temperature, chip formation and product quality in turning AISI-1040 steel at different industrial speed-feed combinations by uncoated carbide insert. The results have been compared with dry machining and machining with soluble oil as coolant. The experimental results indicate that such MQL enables substantial reduction in the cutting temperature, dimensional inaccuracy depending upon the levels of the cutting velocity and feed rate. It was also noted that the chip formation and chip–tool interaction become more favorable under MQL condition. Therefore, it appears that MQL, if properly employed, not only provides environment friendliness but can also improve the machinability characteristics.