Mechanical Properties of New Hybrid Materials: Metallic Foam Filled With Syntactic Foam

Syntactic polymer foam has received intensive attention and extensive application due to its remarkable low cost, lightweight, mechanical properties as well as its thermal, acoustic properties for multifunctional purpose. Electrically conductive polymers have the advantages of light weight, resistance to corrosion, good processability, and tunable conductivity. In a recent separated study, we proposed a novel conductive polymer which was based on the metallic foam filled with syntactic polymer foam. In this study, instead of focusing its unique multi-physical properties, we focus on characterizing the mechanical properties of this new conductive syntactic foam. Before the exploration of this new hybrid foam, an understanding of the mechanical properties is quite necessary. To this end, hybrid foams were prepared by varying the volume fractions of microballoons in the syntactic foam and types of microballoon materials: glass and polymer microballoons. The metallic foam adopted in this work was based on aluminum with an average relative density of 7% (the porosity is about 93%). Both compressive and bending tests were conducted. The current test results may provide the valuable baseline and also facilitate the further understanding of this hybrid foams as a core material in the advanced sandwiched pipe/pressure vessel structures featured by lightweight, impact tolerant, self-monitoring, thermal and acoustic insulation, and electromagnetic shielding.