A 3-DIMENSIONAL MODEL OF CHIP FLOW, CHIP CURL AND CHIP BREAKING UNDER THE CONCEPT OF EQUIVALENT PARAMETERS

Chip control is a major problem in machining processes, especially in finishing operations. Previously, some research in chip control has been done using orthogonal cutting models, however the assumptions made in the models hardly satisfy most practical machining conditions in which the influences of tool corner radius cannot be ignored. The analytical and experimental research presented here deals with a three-dimensional model of chip flow, chip curl and chip breaking. Three features are considered: the geometrical feature, the kinetic feature and the mechanical feature. A set of equivalent characteristic parameters are defined and the relationship between the equivalent parameters and the machining parameters is developed. In addition to theoretical analysis for the equivalent parameters, some of the equivalent parameters are determined by experiment. Finally, a new criterion of chili breakage is given by using the developed model. It is shown that the predicted results agree reasonably well with experimental results.