Surface plastic deformation and surface topography prediction in peripheral milling with variable pitch end mill

Abstract

Peripheral milling with variable pitch end mills is available to improve the surface integrity during final machining. Among the indicators of surface integrity, surface plastic deformation and surface topography are the foremost characteristics. In this paper, two main aspects are included. On the one hand, a unique generic technique in terms of depth of plastic deformation, plastic strains distribution for analyzing the plastic deformations on the work piece is presented. The presented technique applies the problem of the Flamant–Boussinesq in the plastic deformation problem. Through experimental verification, the analytical results have a higher accuracy. On the other hand, the surface generation mechanism in peripheral milling with variable pitch end mills is studied. Corresponding surface generation model, which is used to predict the generated surface topography with incorporating the cutting process parameters and several sources of machining error such as tilting, run-out, deflection of the tool and work piece displacement, is proposed. Through a set of cutting tests, it is confirmed that the presented model predicts the surface texture and roughness parameters precisely. By the sensitivity analysis, Helix angle and feed rate have significant influences on surface topography, while the effects of cutting speed on surface topography can be neglected when the effects of the machining error sources on the behavior and performance of the model are not considered. Among the sources of machining errors, the deflection of the tool has the most significant impact on the surface profile. The sequence is the displacement of the work piece and the run-out of the tool.