Robert B. Ruokolainen

Investigation of Forming Performance of Laminated Steel Sheets Using Finite Element Analyses

Laminated steel sheets have been used in automotive structures for reducing in‐cabin noise. However, due to the marked difference in material properties of the different laminated layers, integrating laminated steel parts into the manufacturing processes can be challenging. Especially, the behavior of laminated sheets during forming processes is very different from that of monolithic steel sheets. During the deep‐draw forming process, large shear deformation and corresponding high interfacial stress may initiate and propagate interfacial cracks between the core polymer and the metal skin, hence degrading the performance of the laminated sheets. In this paper, the formability of the laminated steel sheets is investigated by means of numerical analysis. The goal of this work is to gain insight into the relationship between the individual properties of the laminated sheet layers and the corresponding formability of the laminated sheet as a whole, eventually leading to reliable design and successful forming p...

An Efficient Sandwich Plate Element for Predicting the Vibro-Acoustic Response of Laminated Steel Panels

A New finite element sandwich plate is presented. It is based on discrete displacement approach and allows for both symmetrical and unsymmetrical configurations. The validity and accuracy of the presented element is assessed through comparisons with both tests and classical FE modeling. The tests consist of various configurations of sandwich panels in a coupled plate-cavity system. A parametric study, using the developed element, is finally presented to highlights the effects of skin and core properties on the vibration and radiation of such structures under both airborne and structure-borne excitations.Copyright