Effect of different grinding fluids applied in minimum quantity cooling-lubrication mode on surface integrity in cBN grinding of Inconel 718

Abstract

Inconel 718 (IN 718) is one of the important nickel based alloys that is being extensively used in aerospace industry. Being an aerospace material, surface integrity is of paramount importance due to high risk factor involved in this kind of industry. Superabrasive grinding wheels are believed to be superior over conventional wheels, which can improve the surface integrity of the ground component. Further, minimum quantity cooling lubrication (MQCL) is seems to be a promising technique that can also yield desirable surface quality. Therefore, in the present study IN 718 was ground with single layer superabrasive cBN wheel with neat oil, soluble oil water emulsion and different nanofluids in MQCL mode, and the surface integrity was studied. Flood cooling was also used as a benchmark. Residual stress, ground surface morphology, and surface roughness were studied using X-ray diffraction, scanning electron microscope, and 3D surface profilometer, respectively. Chip morphology was also studied using scanning electron microscope to correlate it with the surface quality of the job. Performance of MQCL neat oil was found to be the best as compared to other fluids in the context of surface integrity due to proper lubrication and grit penetration.