FVM based Methodology for Evaluating Adhesion Wear of Cutting Tools

摘要

In the machining processes, surface quality of the worked pieces depends strongly on the tool conditions. Tool wear has, by that, a determinant influence on the surface finishing quality of the machined products. Tool wear has been commonly associated with the loss of tool material. Standards, procedures and methodologies have been developed for evaluating tool wear under that idea. How- ever, currently, the tool wear concept must be considered in a wider meaning. In effect, nowadays, tool wear must be related to the changes in the cutting tool caused by the machining process. These changes contain both its geometrical and physicochemical prop- erties variations. The first of them involves not only the loss of material but also the incorporation of machined material to the cut- ting tool, as in the secondary adhesion wear, where workpiece material is adhered to the tool in two well-defined zones: rake face, giving rise to the Built-Up Layer (BUL); edge and clearance face, giving rise to the Built-Up Edge (BUE). Up to the present, the evaluation of BUL and BUE has not been satisfactorily solved and, by that, the secondary adhesion tool wear is hardly evaluated. Only some indirect methods can be found based in output variables and parameters (Cutting Forces, Surface Quality Parameters). In this paper, a BUL and BUE measuring methodology, based in the reproduction of BUL-BUE 3D surfaces through Focus Varia- tion Microscopy, has been proposed. This methodology can serve as a first reference for standardizing the evaluation of secondary adhesion tool wear.