Critical Review of Some Previous Work on the Mechanics of the Metal-Cutting Process

Abstract

A review is presented concerning the mechanics of the metal-cutting process where a continuous chip is produced with the absence of a built-up edge on the tool face. It is shown that previous theories which predicted a linear relationship of the form φ = A − B (β − α) between the angle parameters cannot be used to interpret the experimental data. The apparent linear relationships observed in some previous experimental work are thought to be due partly to the method of presentation of the results. It is suggested that a more significant combination of the angle parameters is the difference between the shear angle φ and the rake angle α, that is, (φ − α). It is pointed out that two parameters which can be used to describe the frictional conditions on the tool face are the mean friction stress and the mean normal stress. Since these can vary independently, it is thought unrealistic to group them together as a single variable. It is therefore concluded that the mean angle of friction is insufficient in itself to describe the frictional conditions on the tool face.