Research on Optimizing of circularity and Surface Roughness for Turn-Mill Multitasking Machining

In this study, Taguchi’s robust process design optimizes the turning and milling combined processing. The quality characteristics are surface roughness and circularity. The experiment uses the $L 9\left(3^{4}\right)$ orthogonal table to find the parameters optimized for a target. The control factors used are tool speed (r.p.m.), axial depth of cut (mm), finishing allowance (mm), and C-axis brake pressure $\left(\mathrm{kg} / \mathrm{cm}^{2}\right)$, with roughness and circularity as characteristic targets, analyze and calculate the obtained signal-to-noise ratio (S/N) data to obtain the optimization of quality characteristics. The experimental results show that the optimized surface roughness of quality characteristics is $0.473 \mathrm{~mm}$, and the optimized parameters are Al (5001pm), B2 $(2 \mathrm{~mm}), \mathrm{Cl}(0.6 \mathrm{~mm})$, and D1 $\left(20 \mathrm{~kg} / \mathrm{cm}^{2}\right)$. The circularity is $0.0003 \mathrm{~mm}$, and the optimized parameters are $A 3$ (900r.p.m.), B1 (1mm), C3 (1.4mm) and D2 $\left(25 \mathrm{~kg} / \mathrm{cm}^{2}\right)$. After optimization experiments, the circularity has increased by 67 %, and the surface roughness has increased by 28.8 %. It is also known that a higher tool speed will increase the cutting speed and the tool wear will be relatively greater. After comparing the tool wear of the two characteristic targets, it is found that the tool wear difference of the circularity is $0.039 \mathrm{~mm}$, which is an increase of 59 %. The tool wear difference of the surface roughness is $0.025 \mathrm{~mm}$, an increase of 39 %.