GRINDING OF INCONEL 718 ALLOY WITH AIR-OIL-WATER MIXTURE DELIVERED BY MQL TECHNIQUE

摘要

ⅰ) The conventional coolant technique outperformed the MQL technique in terms of surface finish and hardness variation after machining with radial depth of cut below 30 μm with alumina abrasive wheel. ⅱ) All the surface roughness (Ra parameter) values were below 0.45 (μm, demonstratingthat even the air-oil-water MQL technique can be an environmentally friendly alternative for grinding Inconel 718 alloy when good finishing is the main requirement, although flood cooling can provide even better finishing. ⅲ) Evidence of reduction in hardness was observed after machining with the MQL technique up to 300 μm, irrespective of the depth of cut employed, unlike for conventional method where all the values clustered around the reference hardness values obtained prior to machining. ⅳ) It is not recommended to grind Inconel 718 alloy with depth of cut in excess of 20 μm under the conditions investigated.