Research on Modeling and Simulation of Surface Topography Obtained by Trochoidal Milling Mode with Ball End Milling Cutter

Trochoidal milling mode has small cutting force, high surface quality and productivity, which is widely used in the high speed and velocity machining. Due to a good adaptability and flexible adjustment of orientation, ball end milling cutter is commonly used for multi-axis machining complex surface. However, the processes of part material removal and the machined surface formation is very complicated and difficult to describe because the tooth profile of ball end milling cutter is complex and the direction of cutter trajectory changes continuously in trochoidal milling process. A numerical simulation method is put forward to simulate the surface topography milled with ball end milling cutter which is based on the principle of homogeneous coordinate transformation matrix to establish the locus equation of cutter tooth, and finish the surface topography simulation by improving Z-MAP algorithm. The algorithm quickly obtain the part grid nodes perhaps swept by the cutter tooth within unit time step through the establishment of servo rectangular encirclement and instantaneous scanning quadrilateral of the basic unit of the cutter tooth, and on these bases the part grid node really swept is determined through the angle sum method, and the height coordinate is calculated using the method of linear interpolation according to Taylor formula of multivariate function. The results show that ball end milling surface topography obtained by trochoidal milling is superior to the ordinary straight line milling on the whole. Experimental validation results show that no matter in the case of vertical or tilting machining, surface topography of trochoidal milling with ball end cutter is high consistency with the simulated ones, and the proposed method can predict the surface topography in practical manufacturing. © 2018 Journal of Mechanical Engineering.