(A) new approach to chip curl formation in orthogonal cutting

Abstract

In orthogonal machining with plane face tool, the chip has a natural tendency to curl. And the study of chip curl behaviour can be a considerable help to the methods of chip control in industry when the chip, if uncontrolled, is a great unisance. And this paper is concerned with the mechanism of natural chip curl. The observed facts concerning the chip formation process are briefly explaned and previously published works on chip curl mechanism are examined. An explanation about the chip curl mechanism is presented by choosing a curved shear plane (or shear surface) model and an analytic expression for this shear surface is derived in a simple closed form by introducing a plastically shearing secondary deformation zone in the chip.