A four-node shell element with enhanced bending performance for springback analysis

Springback simulation is comprised of forming stage and springback stage. Since the amount of springback is determined by the residual stress, calculation of stress in forming stage is critical to the accuracy of springback simulation. A new shell element is proposed in this paper to improve accuracy and efficiency of springback simulation by describing complicated bending deformation accurately. It is applied to both explicit FEM and implicit FEM to conduct springback simulation. The present shell element showed twice faster convergence rate than previous shell elements in springback simulation. It implies that very fine meshes, which have been believed to be necessary for springback simulation, can be avoided by using the present shell element, so that overall computational efficiency can be much improved. (C) 2004 Elsevier B.V. All rights reserved.