Estudo da formação de rebarbas no torneamento cilíndrico externo de aço-carbono ABNT 1045

Abstract

The main goal of this work is to study burr formation in externai cylindrical turning of carbon Steel ABNT 1045. It can be identified two kinds of burrs: the entrance burr (Poisson burr or sideflow burr) and exit burr (roll over burr or leaned to feed direction burr). It is studied the effect of cutting speed, feed rate, depth of cut and aproach angle on burr’s geometry - height and thickness, and on its microhardness (exit burr). The experiments were carried out on turning with single point TiN coated Carbide cutting tools, without cutting fluid, and using workpieces in form of flanges. The height and thickness of the burr formed were measured using two different procedures. First, directly from the workpiece using gauge indicator to measure the height. In the second method, small samples were cut out from the workpiece and metallurgical mounts were prepared in resin to be observed in the optical microscope. The results indicates that the machining parameters have effect on burrs geometry, mainly, on the exit burr. The exit burr height is highly affected by depth of cut and entering angle. Feed rate have significant influence on the thickness of burr. It can be observed microhardness variation in the exit burr but the results do not allow any conclusions about the effect of cutting parameters.