Some Characteristics of Foam-Steel Combination Structures for Vehicular Applications

The paper provides some design data for characteristic shapes pertinent to steel-structural foam laminate structures that would be formed from plain steel sheets with the foam added to the steel part in its final shape. For panel type sections, attention was focused on open-faced, flat sandwiches. Panel rigidity was studied in bending and torsion as a function of steel thickness, foam density, and foam thickness. The results are presented in terms of equivalent steel panel thickness and in terms of weight saving compared to solid steel panels of equivalent rigidity. Limited data will also be presented on the effect of steel yield strength and thickness and foam density and thickness on dent resistance of the open-faced panels. With regard to structural applications, data will be presented for maximum load and energy absorption of ultra high strength square tubes loaded in bending. It will be shown that the foam density must exceed some critical value for its use to be weight effective. Some data are also included on the effect of using adhesion promoters or coring a central hole in the foam on its performance.