Geometrical Modelling of a Ball-End Finish Milling Process for a Surface Finish

Abstract

Finish milling with a ball-end mill is a key process in manufacturing high-precision and complex workpieces such as dies and moulds. Due to the complexity of the milling process, it is difficult to observe experimentally the surface microcharacteristics such as the surface topography and roughness of machined workpieces real-time during machining. This necessitates simulation of the process. In this area, the existing related simulation researches focus mainly on scallop heights; few have presented a whole picture of the microcharacteristics of milled surfaces. A comprehensive simulation system has been developed for predicting the surface topographic features and roughness formed in the milling process, and the effect of machining parameters was studied. This paper focuses on the modelling method and theory adopted in the simulation system. The method to improve the calculation accuracy is discussed in detail. The approach to incorporate the effects of the cutting tool run-out and wear is also presented. Experiments are also carried out to verify the simulation results.

Keywords

ball-end finish milling surface microfeatures Z-map

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