Experimental research on the stiffness of cylindrical shallow shell

The introduction of new materials and the use of thinner sheets have led to greater focus on the stiffness of auto body panels in the automotive industry during the last years. In this paper, an experiment test method for determining stiffness was presented. The criterion and research technique of auto body panels stiffness were introduced, and the cylindrical shallow shell modes that could represent auto body panels were investigated. Extensive experiment results, which show the effects of the panel geometry and curvature, material mechanical properties, various forming process conditions and the spring back on the stiffness, were achieved. It can be concluded that panel geometry and curvature significantly influences the stiffness. The forming process plays a beneficial role in stiffness, and reducing the spring back is major potential for increasing the stiffness. (C) 2006 Elsevier B.V. All rights reserved.