Enhanced grindability and mechanism in the magnetic traction nanolubricant grinding of Ti-6Al-4 V

Minimum quantity lubrication with nanolubricants is an efficient and environmentally friendly lubrication method with the greatest potential to replace traditional metal grinding with fluids. However, it faces the technical challenge of insufficient infiltration capacity in complex grinding zones, leading to the deterioration of tribological properties and surface integrity, especially in the large contact length grinding (LCLG) of difficult-to-machine aerospace materials. In this paper, we present a novel magnetic traction nano-lubrication (MTN) method, wherein a magnetic-assisted device is used to generate traction energy for increasing the infiltration capacity of magnetic nanolubricants in grinding. However, the effectiveness and mechanism of MTN grinding have not been studied. First, our results showed that in general grinding, the Fe3O4/graphene nanolubricant showed better cooling and lubrication performance than palm oil, Fe3O4 nanolubricants, and graphene nanolubricants. In MTN grinding, grinding force and grinding temperature had reduced by 35.8% and 66.4%, respectively, with the arithmetical mean height Sa decreasing by 27.5%. Plastic uplift and debris adhesion on the workpiece surface were also eliminated. Second, the improvement in infiltration performance under magnetic field traction was further verified by the LCLG experiment. Finally, the unique infiltration and antifriction mechanism of MTN were analyzed. The MTN technology solves the technical bottleneck of poor surface integrity and provides a solution for the LCLG of materials with high hardness and toughness and low thermal conductivity.