A HIGHER FIDELITY MODELING OF THE CUTTING EDGE OF BALL-END MILLING TOOL

Abstract

Ball-end milling tools have been widely used in machining of complex freeform surfaces. The precision and efficiency of ball-end milling process can be improved by an accurate modeling of the tools, the tools' paths and the machining conditions. However, only rough geometric models have been applied so far, which do not consider the machining conditions and the physical changes. To achieve the best results, an accurate modeling of the cutting edge and the physical behavior of the entire cutter is needed. This paper proposes an articulated model that enumerates both the geometric characteristics and the physical effects acting on the cutting edge-segment of a ball-end milling cutter. The model considers the deformations caused by the milling forces, vibration, spindle eccentricity, together with thermal deformation and wear of the cutter. The mathematical description of the behavior has been transferred into a computational model. The pilot implementation has been tested in a practical application. The first findings show that the proposed theoretical model and implementation provide sufficiently precise information about the behavior of the cutter in virtual simulations; hence it can be the basis of a fully fledged and more efficient planning of milling processes.