Prediction of flexible cutting forces and tool deflections for general micro end mill considering tool run-out and deflection feedback

In this paper, a novel cutting forces and tool deflection prediction methodology for general flexible micro end mill in micro milling is proposed, which includes the effect of exact trochoidal trajectory, tool run-out, and deflection feedback together. A new mathematical model is introduced to determine the instantaneous uncut chip thickness and cutting state of cutting edge element for general micro end mill considering the exact trochoidal trajectory, tool run-out, and deflection feedback. Besides, an iterative calculation method is presented to estimate the flexible cutting forces and tool deflections, and the combined influence of tool run-out and deflection feedback on cutting forces and tool deflections is investigated by using the proposed model. To validate the effectiveness of the proposed methodology for cutting forces and tool deflections in micro milling, the micro slot milling of inclined surface have been conducted on a three-axis ultraprecision machine. The predicted and measured results show that the proposed cutting forces model performs well with the average absolute error of 4.18% in X-direction, and 5.21% in Y-direction, and the proposed tool deflection model performs well with the average absolute error of 9.60% in X-direction, and 10.10% in Y-direction when the exact trochoidal trajectory, tool run-out, and deflection feedback are all taken into account.