Taguchi-Based Optimization of CNC Turning Parameters for Surface Roughness of Al-3Mg Alloy Using a 0.8 mm Nose Radius Tool

Abstract

This research presents a systematic optimization of machining parameters to minimize surface roughness (Ra) in CNC turning of Al-3Mg alloy, utilizing a 0.8 mm nose radius carbide insert. Following the methodology of Taguchi, an L9 orthogonal array was implemented to evaluate the influence of feed rate, cutting speed, and depth of cut. Surface quality was assessed through Signal-to-Noise (S/N) ratio analysis and Analysis of Variance (ANOVA) to quantify factor contributions. Results demonstrate that feed rate is the primary determinant of surface finish, accounting for 83.59% of the total variance, while cutting speed and depth of cut contributed 6.37% and 3.91% respectively. The optimal parametric combination was identified as a 0.3 mm/rev feed rate, 700 rpm cutting speed, and 0.5 mm depth of cut, resulting in a predicted roughness of 14.511 μm. These findings align with established manufacturing principles regarding the quadratic relationship between feed rate and surface geometry.