Novel uses of SiO₂ nano-lubrication system in hard turning process of hardened steel AISI4140 for less tool wear, surface roughness and oil consumption

Hardened steel AISI 4140 material is commonly used to produce automotive parts such as shafts, gears and bearings. Machining this material significantly increases the temperature in the cutting zone and is critical in deciding workpiece quality. Though cutting fluids are widely employed to dissipate the heat in machining, they threaten the ecology and health of workers. Hence, there arises a need to identify eco-friendly and user-friendly alternatives to conventional cutting fluids. Modern tribology has facilitated the use of a nano-lubrication system. For this purpose, a novel uses of nano-lubricants in minimum quantity lubrication (MQL) system were studied. In the present work, a mist of SiO₂ nano-lubrication was used and applied by air pressure in turning of hardened steel AISI4140. In this research work, the optimum SiO ₂ nano-lubrication parameters to achieve correct lubrication conditions for the lowest tool wear and best surface quality were investigated. These parameters include nano-lubricant concentration, nozzle angle and air carrier pressure. The Taguchi optimization method is used with standard orthogonal array L₁₆(4)3. This research is investigating on the new and novel uses of SiO₂ nano-lubricant by conducting analysis on tool wear and surface roughness using fuzzy logic and response analysis to determine which process parameters are statistically significant. Besides, these analyses were conducted in order to prove the effectiveness of nano-lubricant. Finally, confirmation tests were carried out to investigate optimization improvements.