Analytical and Numerical Calculation of the Force and Power Requirements for Air Bending of Structured Sheet Metals

Abstract

Structured sheet metals with regular bumps offer higher stiffness compared to smooth sheet metals. They can be produced by a hydroforming process. The application of the structured sheet metals, however, is inhibited by the lack of knowledge for the subsequent processing steps. In this paper, the force and power requirements for air bending of structured sheet metals are calculated with a Finite Element Simulation (FE) and an analytical approach. In the first step, the hydroforming manufacturing process of the structured sheet metals is simulated in order to predict the exact geometry and the change in the material properties. Following, air bending simulations have been done taking into account the results of the hydroforming simulation. The FE-Simulations have been carried out with the software package LS-DYNA. The simulation models are validated with the optical displacement measuring system ARGUS and by a series of bending tests. For the analytical calculation the model based on the bending theory is adapted by simplifying the cross section of the structured sheet metals. The results of the FE-Simulation, the analytic calculation and the experiments are compared. The advantages and disadvantages as well as the application areas of the considered methods are indicated.