Sustainable Machining: MQL Technique Combined with the Vortex Tube Cooling When Turning Martensitic Stainless Steel X20Cr13

For the purpose of contributing to sustainable machining, aim was investigate turning martensitic stainless steel X20Cr13 under alternative cooling and lubrication techniques. The minimum quantity technique in combination with vortex tube cooling, as determined optimal method using Taguchi-based entropy weighted grey relational analysis (compared emulsion technique) previous research when X20Cr13, were applied this accordance Box–Behnken design. is investigate, applying condition (minimum + vortex) design, which parameters have a significant influence on reducing surface roughness Ra Rz also tool life (T). cutting speed (vc = 260, 290 320 m/min), feed rate (f 0.3, 0.35 0.4 mm/rev) depth cut (ap 1, 1.5 2 mm) selected parameters. An exponential model for Ra, T obtained. According ANOVA results, it can be seen that only had Rz. life, according all three (cutting speed, cut) Experimental results compared mathematical presented diagrams. A new nozzle designed allow micro-droplets from MQL unit chilled compressed air connected one stream (single-channel system) before entering zone, thus allowing simultaneous cooling. used system an flow 708 L/min inlet pressure 0.69 MPa, temperature drop −29 °C achieved regard 21 °C. Therefore, recommended X20Cr13.