Investigation of the effect of Minimum Quantity lubrication technique on performance of the grinding of HSS

In grinding operation، cutting fluid is utilized for lubrication، cooling، chip removal from contact zone and also cleaning of grinding wheel. Despite these advantages، grinding fluids make many economic and environmental issues. On the other hand، dry grinding generally leading to thermal damages and reduction of surface quality level. Minimum Quantity Lubrication (MQL) technique is a new approach to elimination or reduction of cutting fluids that improves grinding performance by efficient penetration to the cutting zone. In this paper، in order to investigate the effect of MQL on grinding of steels، raw and hardened High Speed Steel have been selected. Grinding performance such as tangential grinding force، friction coefficient، roughness and morphology of the ground surface and chip form in three states of dry، conventional fluid and MQL have been studied and compared. The results show that MQL technique in comparison with the others lead to improvement of surface quality and also reduction of tangential grinding force and friction coefficient in hardened steel، but in the case of raw steel despite of reduction of tangential grinding force and friction coefficient، the surface quality is worst.