A semi-analytical method for the springback prediction of thick-walled 3D tubes

摘要

The aim of this paper is to investigate the deformation and springback behavior of 3D tubes under complex stress conditions. We proposed a new semi-analytical method to predict the springback behavior of 3D tubes. In the new method, discretization and approximation are implemented on the tube axis so that the deformation parameters (bending radiuses and twisting angles) can be derived. Based on the discretization and approximation, a theoretical model is proposed to calculate the stress distributions and residual deformations. The new method is applied on a typical 3D tube for springback prediction, and comparison between theoretical and experimental results shows a remarkable agreement. Additionally, it is also found that the radii after springback will decrease inversely with the increase of twisting angle, and this tendency will become clearer when the bending radius increases. (C) 2016 Elsevier Ltd. All rights reserved.