Formation and simulation of burr in metal cutting

A burr formation FEM has been presented in this paper based on ANSYS/LS-DYNA. From the simulation results of strain and stress distribution, the mechanism of the burr formation process is analyzed. Based on the stress and strain contours of simulation results, with the progressive change of geometry at the edge of workpiece, three stages of burr formation are investigated, i.e., steady-state cutting, pivoting, final burr development stage. According to the simulation results in steady-state cutting stage, it can be clearly seen that the primary shear zone be formed around the tool tip, the accuracy of the model can be checked from this stage. In pivoting stage, negative shear angle and the forth deformation zone is proposed, and the pivoting point B whose location is proportional to burr thickness is observed. In final burr formation stage, with different crack prolongation mechanism two types of burr that is positive and negative burr can be generated on workpiece edge. To verify burr formation process, the experiments with different materials and different cutting conditions are carried out on refitted milling machine. Factors that influence burr formation are analyzed from experimental results.