Comprehensive Analysis of Cutting-Force Components in Milling Using RQA: Effect of Edge Geometry and Process Parameters

This study investigates the influence of cutting edge geometry (continuous, serrated, and wavy) and selected machining parameters (cutting speed <i>v_c</i>, feed per tooth <i>f_z</i>, and radial infeed <i>a_e</i>) on cutting-force components and dynamic behavior during the milling of an AlZn5.5MgCu aluminum alloy. The analysis was based on box plots and Recurrence Quantification Analysis (RQA) applied to the cutting-force signal. The results demonstrated that serrated and wavy-edge tools generated significantly lower values of the normal force component F_fN-up to -57% on average-compared to the continuous-edge tool, particularly at lower <i>f_z</i> and <i>v_c</i>, indicating enhanced process dynamics. At higher <i>a_e</i> values, however, these tools induced increased signal variability-up to 300% greater-suggesting potential resonance excitation. RQA indicators, such as DET, Lmax, and LAM, revealed a strong dependence of system dynamics on tool edge geometry. Linear Discriminant Analysis (LDA) confirmed that RQA measures effectively distinguish between cutting-edge types. The study concludes that tooldge geometry substantially affects milling process stability and can be purposefully selected to optimize performance under varying machining conditions.