Effect of material removal on workpiece dynamics in milling: Modeling and measurement

Abstract

This paper provides an investigation on the workpiece dynamics variation arisen from the material removal in both modeling and measurement aspects. To this end, finite element analysis, receptance coupling and inverse receptance coupling are employed in the modeling of the workpiece dynamics considering the material removal during the milling process. The fixed-free workpiece is divided into three components as machined, unmachined and fixed boundary condition in the receptance coupling model. The fixed boundary condition receptances are determined through the inverse receptance coupling to mathematically acquire the fixed boundary condition of the experimental setup flexibility that causes significant difference between the modeling and measurement results. Besides that, with the novel application of the inverse receptance coupling, it is analytically predicted the variation of the workpiece natural frequency as the material is removed in the milling process. This new application has been verified with the experimental studies conducted on a single degree of freedom flexure stage and a good agreement between the predicted and measured natural frequencies has been achieved. Furthermore, it has been observed that the receptance coupling results agree well with the ones obtained via the finite element analysis in the modeling of the fixed-free workpiece dynamics.