The present paper highlights results from the priority program "Cellular Metals" of the Deutsche Forschungsgemeinschaft (DFG SPP 1075). Aluminum foams are still a relatively new class of materials and offer a high potential for lightweight construction. Especially as core structures in sandwich materials aluminium foam benefits from their excellent properties regarding density, stiffness and energy absorption behavior. In contrast the usage of foams as a construction material is significantly limited by their low forming characteristics at ambient temperature. The implementation of a high-temperature-forming process in the region of the melting interval of the foam alloys can remove these restrictions. Reduction of yield stress and ultimate strain at high temperatures allows forming of complex shaped aluminum foam components whereas even the cover sheets can act as the forming tools. In conjunction with a suitable joining technology to apply the cover sheets, the use of cost-effective melt route aluminum foams enables manufacturing of lightweight sandwich structures for a wide range of applications. In this paper, investigations of the compression behavior of melt foamed aluminum foams under temperature load are presented. A process window for forming cellular aluminum at high temperatures in a rectangular cup tool is shown for manufacturing core structures for sandwich parts. In addition, experimental results concerning joining of the foam core and the cover sheets for manufacturing sandwich components are described.
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