Effect of combined cryogenic cooling and minimum quantity lubrication on machining characteristics of SS 316L

Abstract

Implementing new approaches, such as cryogenic cooling, can solve the temperature-related challenges in machining while eliminating disposal problems, hazardous emissions, and associated problems. In this context, the comprehensive machinability evaluation of SS 316L utilizing hybrid minimum quantity lubrication (MQL) + LCO₂ is presented by comparing the results of measured machining responses with dry, flood, MQL, and LCO₂ cutting environments. Hybrid machining significantly reduced Ra values by up to 40.63, 32.15, 9.53, and 17.37%, compared to dry, flood, MQL, and LCO₂ conditions. Similarly, compared to dry machining, approximately 44% reduction in cutting temperature is achieved with improved cooling and lubrication during MQL + LCO₂. The outcomes demonstrated that the MQL + LCO₂ application efficiently reduced frictional forces and reduced tool wear by up to 30.77% compared to dry machining. Relatively small diameter helical chips with surfaces free from scratches are produced under MQL + LCO₂. The outcomes demonstrated the efficacy of MQL + LCO₂ in improving the machining performance of SS 316L. The sustainability aspect of the presented approach is evaluated by considering total machining costs and carbon emissions.