Predicting workpiece dynamics in milling of thin-walled structures using three-dimensional spectral element method

Official URL: https://dx.doi.org/10.1016/j.tws.2025.113851

This paper addresses the challenge of milling thin-walled structures, which are highly valued for their lightweight and robust characteristics yet are prone to process instabilities due to chatter-induced vibrations. These vibrations adversely affect surface quality and dimensional accuracy during material removal. Traditional finite element analysis (FEA) methods have been widely used to predict the dynamic behavior of these components; however, they often require detailed meshing and become computationally expensive when continuously updating the workpiece model. To overcome these limitations, we introduce a novel three-dimensional spectral element method (3D-SEM) based on the spectral Chebyshev approach. This method efficiently computes elemental stiffness and mass matrices and predicts the evolving frequency response functions (FRFs) at the tool–workpiece interface, which are critical for evaluating chatter stability. The performance of the proposed 3D-SEM approach is demonstrated through comparisons with FEA simulations and experimental results, showing that it delivers accurate predictions of workpiece dynamics at a significantly reduced computational cost compared to traditional FEA.