Effect of the dynamic stiffness of a five-axis machine tool on the quality of sculptured surface

Abstract

To achieve high quality of sculptured surface, a five-axis machine center must have excellent dynamic behavior. This article gives a new way to characterize and present the performance of machine center on milling sculptured surface which is constrained by the dynamic stiffness. First, the formation mechanism of surface quality is explained in intermittent milling process. It is mainly affected by the vibration frequency of cutting behavior. Second, the concept of dynamic stiffness of machine center is proposed and calculated based on the movement of multi-axis. To elaborate such effect, the map of dynamic stiffness on a sculptured surface, S part is obtained. The change of stiffness causes the different vibration frequency and then leads to different surface quality. Finally, experiments are conducted on S part by microscope and the waviness measurement. The results demonstrate the proposed method is very close to the true one. Presenting, measuring, and controlling the surface quality are easy for the user to understand the challenging performance of the machine center on milling sculptured surface.