Title: Progressive multistep press forming of a truss core panel for floor structure of electric vehicle

Authors: Chenghai Kong; Xilu Zhao; Ichiro Hagiwara

Addresses: Department of Mechanical Engineering, Saitama Institute of Technology, 1690 Fusaiji, Fukaya, Saitama, Japan ' Department of Mechanical Engineering, Saitama Institute of Technology, 1690 Fusaiji, Fukaya, Saitama, Japan ' Meiji Institute for Advanced Study of Mathematical Sciences, Meiji University, 4-21-1, Nakano, Tokyo, Japan

Abstract: The truss core panel is a composite of double-layer triangular core panels, and has characteristics of high strength and low weight. However, problems of fracturing and a limited forming height arise because of the complex shape of the panel. From research on a hemispherical shape transition mould, we propose a new pyramid transition shape for the die used in the progressive press forming. Employing the finite element method, we simulated progressive press deforming and determined the effectiveness of forming. The new mould greatly improves the thickness distribution and forming height of the truss core panel. Additionally, we manufactured a model of the die and processed a truss core panel, and compared the thickness distributions of simulated and processed truss core panels. The thickness distributions of simulated and manufactured panels were similar, demonstrating that simulation can be used to study the forming problem of a truss core panel.

Keywords: electric vehicle; lightweight; truss core panel; simulation and experiment; progressive multistep press forming; mould design; hemispherical transition mould; pyramid transition mould.

DOI: 10.1504/IJVP.2018.090960

International Journal of Vehicle Performance, 2018 Vol.4 No.2, pp.200 - 217

Received: 08 Aug 2017
Accepted: 17 Sep 2017

Published online: 04 Apr 2018 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article