Analysis of Tool Wear by Using a Cutting Bending Moment Model for Milling Processes

In this study, we developed a bending moment model that considers the cutting forces acting on a sensory tool holder along the rotational direction. The polar plot of the bending moment during cutting can be used to investigate the cutting behavior. Cutting processes with different cutting depths and widths result in different polar plots, as verified experimentally. To evaluate the effect of tool wear on the polar plot, the bending moment equations were modified to incorporate the developed tool wear model. The simulation results indicated that tool wear can increase the size of the polar plot and vary the angle of the plot. By examining the change of this angle, one can determine the level of tool wear. The experimental results of this study indicated that the derived equation can predict the tool wear behavior with an average accuracy of 84%. Thus, the proposed integrated model enables the accurate prediction of tool wear. Consequently, the polar plot can feasibly be used to detect the level of tool wear.