Abstract This work examines the optimization of turning parameters across various lubrication environments, that is, mineral oil, biodiesel, and biodiesel augmented with multi‐walled carbon nanotubes (MWCNTs), utilizing Taguchi design and Response Surface Methodology (RSM). The influence of spindle speed, feed rate, and depth of cut on material removal rate (MRR) was methodically examined. Analysis of variance (ANOVA) revealed that spindle speed is the most significant metric under biodiesel lubrication, but depth of cut is predominant under biodiesel–MWCNT settings. Biodiesel and nano‐augmented biodiesel exhibited greater machining performance relative to mineral oil, due to enhanced viscosity, improved lubricity, and the creation of a tribo‐film at the tool–workpiece interface. These methods markedly diminished cutting forces, tool wear, and surface roughness. The optimization results indicated that the minimal material removal rate (MRR) occurred at a feed rate of 0.2 mm/rev, a spindle speed of 1036 rpm, and a depth of cut of 2.47 mm, with experimental validation closely aligning with anticipated values, thereby affirming the reliability of the generated model. Scanning electron microscopy validated these findings, revealing improved surface integrity, with biodiesel–MWCNT lubrication yielding the smoothest machined surfaces. The findings underscore the wider ramifications of utilizing nano‐augmented biodiesel lubricants, such as less reliance on petroleum‐derived cutting fluids, enhanced process sustainability, and conformity with eco‐friendly manufacturing standards. The study confirms biodiesel‐based nanolubricants as a realistic, high‐performance alternative for sustainable turning operations, optimizing productivity, surface quality, and environmental responsibility.
Singh et al. (Tue,) studied this question.