The Effect of Al2O3-MWCNT Hybrid Nanofluid on Surface Quality in Grinding of Inconel 600

Grinding is finishing process aimed at achieving surface quality and dimensional accuracy in workpieces with tight tolerances especially from materials with a high degree of hardness and strength. The grinding process of superalloys is faced with problems and challenges caused by the generation of excessiveheatas well as the adhesion of workpiecematerialon the grinding tool. Therefore, in-depth research is still under way to introduce and develop new techniques for optimization of output parameters in the grinding of superalloys. One of such techniques is to apply minimum quantity lubrication (MQL) using nanofluids. In this research, we study the effect of using a type of mixed nanofluid comprising multiwall carbon nanotubes (MWCNT) and nano-aluminum oxide (Al2O3) on the surface quality in the grinding process of Inconel 600.For this purpose, the input parameters of the process are first determined. Following that, the design of experiments were performed based on full factorial method and the, grinding experiments were conducted accordingly to study the effect of various parameters including the nanoparticles size , volume concentration, and mixing ratio on surface quality of the workpiece. Based on the results obtained from this study, while using the vegetable oil for MQL with nanofluids, the highest surface quality with Ra=0.15µm is achieved by applying a nanofluid with a mixing ratio of 75% -25% for Al2O3 -MWCNT nanoparticles, volume concentration  of 0.6%, and with size of 20 nm and 15 nm for Al2O3and MWCNT nanoparticles, respectively.