Hybrid foams consist of two different interpenetrating or particulate-embedded foam-material classes and, therefore, an enhanced multifunctionality of the material and of the final product can be expected. This paper illustrates the concept of hybrid foams with two selected examples. The cells of an open-cell steel host-foam are filled either with a polymer foam or a newly developed direct ceramic foam.

The results of compression tests and non-destructive resonance-frequency-damping analyses are presented. An improvement in the deformation is observed for the metal-polymer hybrid foam, while the deformation behavior changes from brittle to ductile for the metal-ceramic hybrid foams. Additionally, the damping and Young's modulus of the metal foam are enhanced by the interpenetrating direct foamed ceramic.