Analysis of Vibrations During Trochoidal Milling of AZ31 Magnesium Alloy Using Different Tool Holders

This paper presents the analysis of vibration measurements performed on AZ31B alloy for different tool holder types under trochoidal tool paths. The principal aim of the study was to determine the influence of selected technological parameters (cutting speed vc and feed per tooth fz), together with tool holder type (ER, shrink-fit and hydraulic), on selected measures of machining stability. The analysis encompasses the Peak-to-Peak (P-P) value, the Root Mean Square (RMS) value, Composite Multiscale Entropy (CMSE), the Fast Fourier Transform (FFT) and recurrence plots (RP) analysis. The results demonstrate that vibration characteristics depend on both machining parameters and tool holder type. Increasing feed per tooth generally increases vibration amplitude, whereas CMSE provides complementary information on signal irregularity and the relative contribution of periodic and irregular components. Frequency-domain and recurrence analyses reveal differences in the dynamic response of the investigated tool holder systems. The hydraulic holder generally exhibits lower vibration amplitudes and less pronounced harmonic components, consistent with its favorable damping characteristics. Considering the measured vibration amplitudes and complementary signal characteristics, cutting speeds of 400 and 800 m/min are recommended under the investigated conditions. The results also demonstrate the value of combining amplitude-based and nonlinear signal analysis for a more comprehensive assessment of machining dynamics.