Optimization of Cutting Parameters in MQL Flat Surface Milling of SKD11 Steel

In this study, the multi-response optimization in flat surface milling of SKD11 steel using MQL (minimum quantity lubrication) method was addressed. The cutting parameters (input variables) are the spindle speed (S), the depth of cut (ap), and the feed per tooth (fz), and the responses are the surface roughness (Ra) and the cutting power (Pc). The goal is to determine the optimal parameters for minimizing both the surface roughness and the cutting power. For this purpose, the experiment was designed by using the response surface methodology (RSM). Fifteen runs have been conducted to measure the experimental data. The predictive models of Ra and Pc were then developed and evaluated by using the ANOVA. Finally, the optimization problem was resolved by using the desirability function (DF). The results show that the optimal cutting parameters, including S = 1599 rpm, fz = 0.02 mm/z, and ap = 0.1 mm, corresponding to DF = 0.986, allow reducing 31 of the surface roughness and 82 of the cutting power in comparison to the worst case where the cutting power exhibits the highest value. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.