Cutting Force Simulation in Milling of Tapered Wall with Barrel End Mill

Abstract

The machinings of aircraft parts and die molds highly require fine surfaces at high production rates in terms of reliability. Barrel end mills having excessively large curvatures on the side cutting edges have recently been applied to finishing of tapered workpiece walls with respect to the cutter rotation axes. Because a large curvature of the cutting edge reduces the cusp height, the tools finish surfaces with small cusp heights in large axial pick feeds. However, in milling with the barrel tool, the cutting force loading in the direction of tool radius increases with the cutting area along the edge. The machining accuracy is deteriorated by tool deflection due to a large cutting force. The wave form is also left on a surface with the tool vibration. Therefore, the cutting parameters should be determined with controlling the cutting force and its direction in milling with the barrel tool. The paper discusses the cutting forces in milling of tapered walls with a barrel end mill in the cutting simulation. The cutting forces are analyzed in the chip flow models interpreted as a piling up of orthogonal cuttings. The shear angle, the shear stress and the friction angle in the cutting model are discussed with the chip flow model. The cutting force characteristics are discussed for the taper angle of the workpiece.