Effect of Tool Path Complexity on Top Burrs in Micromilling

Burr generation during micro milling operation is one of the major problem that poses challenge before engineers. The deburring operations performed in macro milling cannot be utilized in micro domain as this can affect the dimensional accuracy and possibly, damage the machined surfaces. However, the burr dimensions could be reduced by selecting appropriate machining parameters. Most of the studies done so far are focused on straight slot milling operations, while the complex tool paths, which are more often used in the industrial domain, have not been studied adequately. Therefore, the present work involves a detailed experimental analysis of burr formation in micro milling considering the effect of curvature in the tool path. The experiments performed are of two types. The Type I experiments investigate the top burrs as a function of tool path and machined length. The Type II experiments investigate the effect of machining parameters on the formation of burrs in both straight and curved paths. The burr values are found to increase with the curvature for the top burrs because of the increased plowing region due to the curvature effect. It is also noticed that burr dimensions at lower feed values are more in straight slots whereas, at higher feed values, circular tool paths here resulted in more burrs. Minimum burrs are observed at a depth of cut of 20 mu m. (C) 2019 The Authors. Published by Elsevier B.V.