In machining processes,researchers are actively engaged in exploring minimum quantity lubrication (MQL)as a possible alternative to traditional flood cooling owing to economic and ecological concerns.The search for eco-logically safe lubricants has attracted the attention of sci-entists looking to use vegetable oil as a lubricant.The nanofluid MQL technique with biodegradable oils as the base is a relatively new method with the potential to replace mineral oils.In the present study,the grinding of Inconel-718 alloy was investigated using nanofluid MQL(NFMQL) with biodegradable oils as the base.Nanofluids are composed by dispersing 0.5% (mass fraction) and 1%(mass fraction) of CuO nanoparticles in vegetable oil.The surface morphology,G-ratio,forces,and grinding energy were examined under pure MQL,NFMQL,and dry and flood lubrication conditions.The experimental results indicated that the nanofluid MQL significantly improved the machining performance.Owing to the polishing and rolling effect of nanoparticles on the tool work interface,a surface finish under a 0.5% (mass fraction) nanofluid was found to be better than pure MQL-dry and flood lubrication conditions.The NFMQL technique with 1% (mass frac-tion) CuO nanoparticles with palm oil as the base helped in achieving a better evacuation of chips from the grinding zone,leading to a better surface finish with a high material removal rate along with less energy consumption compared to flood and dry grinding.