Sustainable Control of Optimized Coolant Quantity Using an Effervescent Atomizer for Enhanced Machining Performance

This study investigates the use of an effervescent atomizer during the turning of AISI 304 austenitic stainless steel. The main objective is to optimise the coolant quantity (OCQ) in order to improve cooling performance, surface quality, and machining sustainability. Machining AISI 304 is often challenging because its high ductility and low thermal conductivity tend to generate excessive heat and lead to poor surface integrity. In this work, important machining parameters such as air velocity, spindle speed, and coolant velocity were varied in a systematic manner. Their influence on cutting temperature, surface roughness, and spray angle was examined. The results showed that effective atomisation occurred at an air velocity 43.89 m/s, producing a spray angle of 12.34 0 . At this condition, the coolant delivery was well controlled, and sufficient cooling was achieved at the cutting zone. A significant reduction in cutting temperature was observed. The temperature dropped to 38.22° C, whereas values between 59-76°C were recorded under conventional flood cooling and temperature as high as 3510C occurred during dry machining. The improvement in cooling also resulted in better surface finish. The minimum average surface roughness obtained was 0.19µm and 0.18 µm which correspond to improvements of about 10% compared with flood cooling and 23% compared with dry machining. Overall, the effervescent atomization approach provided efficient heat removal and adequate lubrication at the tool-workpiece interface while using a lower amount of coolant. This reduction in coolant consumption, together with improved machining performance, highlights of the method for more sustainable machining operations. The results validate the potential of OCQ-based effervescent atomisation as a cost-effective, environmentally sustainable, and high-performance cooling strategy for precision machining of stainless steel, contributing to lower coolant waste and energy usage.