Effect of the chip thickness and the exit angle on the burr formation and break-out of the workpiece edge in the case of milling

Abstract

The milling processes often cause defects on the workpiece edge, such burr and break-out which significantly affects the part quality. The burr formation can be controlled during the process with the adjustment of appropriate parameters. The planar exit angle (EA) and the exit order have a promising effect on burr formation. However, the accurate calculation of the EA is difficult, moreover, the uncut chip thickness at the exit point also depends on the EA value. The former researches dealt only with the EA but the dependent uncut chip thickness was neglected. The aim of the current research is to investigate the burr formation at the face milling of AlSIMg7. During the research, the effect of the EA and uncut chip thickness is examined as a new approach, independently of each other. During the experiments, the size of the burr and the edge break-out is measured by an image processing-based method. The results showed that the uncut chip thickness at the exit point has a considerable effect on burr formation. Based on the experimental results, it can be stated, that the distribution of burr size and edge break-out is not normal. The behaviour of burr is quite complex and can only be described with statistical methods. The distribution of the examined defects can be approximated by the combination of two or three probability density functions.