Influence of nano-minimum quantity lubrication with MoS2 and CuO nanoparticles on cutting forces and surface roughness during grinding of AISI D2 steel

Abstract

Environmental side effects of machining lubricants are the main reasons for the progressive development of utilizing the minimum quantity lubrication (MQL) method instead of conventional methods. Owing to the high specific energy of cutting and generation of more heat in grinding, the MQL technique has a lower efficiency than conventional methods. However, by adding nanoparticles to the base oil, the lubrication efficiency in grinding can be enhanced. In this research, grinding of cold work tool steel AISI D2 was studied using a MQL technique by adding MoS2 and CuO nanoparticles to two types of vegetable-based oils: colza and soybean with different concentration percentages, and their effects were examined on the cutting forces (normal and tangential forces) and surface roughness. The results indicated that the values of normal force and tangential forces diminished by 19 and 35 % when using CuO nano powder in soybean base oil with a concentration of 4 % and MoS2 nano powder in soybean base oil with a concentration of 2 %, respectively. Furthermore, when using CuO nano powder in colza base oil and with a concentration of 2 %, the surface roughness had a significant reduction of 77 % in comparison with pure oil as a grinding fluid.