Specific Energy and G ratio of Grinding Cemented Carbide under Different Cooling and Lubrication Conditions

Workpiece surface integrity deterioration is a bottleneck in minimum quantity lubrication (MQL) grinding cemented carbide. However, nanofluids prepared by adding nanoparticles with excellent antifriction and antiwear properties achieve improved lubrication characteristics. In this study, a surface grinding experiment under four working conditions (i.e., dry, flood, MQL, and nanofluid minimum quantity lubrication (NMQL)) with cemented carbide YG8 is conducted to confirm the effectiveness of NMQL grinding. Results show that the minimum specific grinding force (F-t' = 13.47 N/mm, F-n' = 2.84 N/mm), friction coefficient (mu = 0.21), specific grinding energy (U = 17.02 J/mm(3)), and the largest G ratio of 6.52 are obtained using NMQL grinding. Furthermore, no evident furrow and large deformation layers are found on the surface of the workpiece. Moreover, the scanning electron microscope (SEM) images display that the debris is strip-shaped and slenderer than that under the other working conditions. Meanwhile, the blockage of the wheel pore is improved. Therefore, the validity of NMQL in grinding cemented carbide is verified.