Fabrication of functionally radial graded metallic foam

Abstract

Radial graded structures in biological materials, e.g. bones, are lightweight and exhibit good mechanical properties. This paper developed a novel method to fabricate a functionally radial graded aluminum foam. In this method, a sequential solidification was applied from the periphery to the inner on the foaming aluminum melt to obtain a radial gradient. The graded foams were then served as fillers for thin-walled tubes. Quasi-static compressive tests were conducted on the foams and foam-filled tubes. The results indicated that the graded foam-filled tubes exhibited improved crushing resistance and specific energy absorption, compared to the uniform foam-filled tube with similar weight.