Study on nonlinear cutting forces phenomenon of difficult-to-machining materials

To investigate the nonlinear phenomena of cutting forces when machining difficult-to-machining materials in the high-speed cutting process, system experiments by factorial design and Latin hypercube sampling design were conducted. The cutting force nonlinear characteristics were analyzed in time domain and frequency domain through wave-let analysis and power spectrum analysis. Experiments indicated that in the high-speed milling process, the characteristic curves of primary cutting forces could not strictly maintain their linearity with the variation of cutting parameters, the effect of one cutting parameter on primary cutting forces is sensitive to the combination of cutting parameters, and a lower frequency periodic signal appears when the cutting speed is above 471 m/min (spindle speed is 3000 r/min).