Finite difference simulation and experimental investigation: effects of physical synergetic properties of nanoparticles on temperature distribution and surface integrity of workpiece in nanofluid MQL grinding process

Abstract

Application of nanofluids in minimum quantity lubrication (MQL) system in grinding has been proven as an effective approach to counter the negative effects of high temperature evolution in grinding process. However, the cooling and tribological properties of nanolubricants are physical synergetic as the morphology, atomic structure, and physical properties of nanoparticles are determining factors on their performance in MQL systems. Graphite and CuO nanoparticles are representatives of nanoparticles with different atomic structures and physical properties. In this study, a finite difference model based on exponential distribution of moving heat source in wheel-workpiece contact area has been developed to determine the energy partition and temperature distribution of workpiece in nanofluid MQL grinding process using graphite and CuO nanofluids as lubricants. In order to study the effects of atomic structures of nanoparticles on the tribological properties of nanofluids, surface roughness and SEM images of ground surfaces have been evaluated. The results showed that CuO nanofluids with rolling action of nanoparticles in the contact area provide lower energy partition and better surface quality of workpiece in comparison with that of graphite nanofluids with sliding mechanism of atomic planes of nanoparticles at the wheel-workpiece interface during grinding process.