Analytical prediction of the chip rack-flow angle in machining with restricted contact grooved tools

This paper develops a new analytical model to predict the chip back-flow angle in machining with restricted contact grooved tools. The model is derived from a recently established universal slip-line model for machining with restricted contact cutaway tools. A comprehensive definition of the chip back-flow angle is presented first, and based on this, a quantitative analysis of the chip back-flow effect is established for a given set of cutting conditions, tool geometry, and variable tool-chip interfacial stress state. The model also predicts the cutting forces, the chip thickness, and the chip up-curl radius. A full experimental validation of the analytical predictive model involving the use of high speed filming technique is then presented for the chip back-flow angle. This validation provides a range of feasible/prevalent tool-chip interfacial frictional conditions for the given set of input conditions.