A new approach to the modeling of oblique cutting processes

A new upper-bound model that incorporates force equilibrium parallel to the cutting edge is proposed for oblique cutting operations. The energy approach is framed in terms of the normal shear angle and two new fundamental variables that characterize the energy requirements of the oblique cutting process. SLIP is a kinematic variable and is defined as the ratio of the shear velocity imparted to the chip on the shear plane parallel to the cutting edge, to the incoming velocity in the same direction. RATIO is a force-based variable and is defined as the ratio of the friction force on the rake face to the resultant shear force in the shear plane. Calibration of the model for either real time identification purposes or for process planning/optimization requires experimental force data but no shear angle data, making it very suitable for the analysis of cutting operations with non-straight cutting edges. The relationships between SLIP, chip flow angle, and RATIO are shown to be remarkably consistent over a very wide range of inclination and normal rake angles. Finally, the authors demonstrate the success of the model using existing experimental data.