Applicability of cutting fluids with nanoparticle inclusion as coolants in machining

Heat liberated and the friction associated with the cutting process ever pose a problem in terms of tool life. Cutting fluids have been the conventional choice to address the problem. However, environmental hazards posed by the fluids have limited their usage, giving rise to minimum quantity lubrication. Nevertheless, its capability to carry away the heat and provide adequate lubrication is limited. In view of the above problems, nanofluids have gained prominence. Nanofluids, with their cooling and lubricating properties, have emerged as a promising solution. This article deals with characterizing changes in the heat transfer capacities of nanofluids with the inclusion of nanoparticles in the cutting fluids. To estimate the prevalent temperatures in machining, a facing operation is carried out under constant cutting conditions in a dry state and using conventional cutting fluid as coolant. Heat transfer coefficients are estimated using the analogy for flow over flat plates in all lubricating conditions. The temperatures calculated using the estimated heat transfer coefficient for conventional cutting fluid are compared with the experimental observations to validate the methodology. Temperature profiles are simulated using ANSYS 5.4 to infer on the suitability of the coolants in enhancing machining performance. Nanoparticle inclusion is found to be beneficial in improving the coolant properties. Nevertheless, the high cost of nanoparticles may appear to be prohibitive and hence minimum requirement of inclusion is estimated.