Aluminum alloy matrix syntactic foams were produced by inert gas pressure infiltration. Four different alloys and ceramic hollow spheres were applied as matrix and filler material, respectively. The effects of the chemical composition of the matrix and the different heattreatments are reported at different strain-rates and in compressive loadings. The higher strain rates were performed in a Split-Hopkinson pressure bar system. The results show that, the characteristic properties of the materials strongly depends on the chemical composition of the matrix and its heat-treatment condition. The compressive strength of the investigated foams showed a limited sensitivity to the strain rate, its effect was more pronounced in the case of the structural stiffness and fracture strain. The failure modes of the foams have explicit differences showing barreling and shearing in the case of quasi-static and high strain rate compression respectively.

We utilize spin-casting and ultraviolet (UV) light-induced polymerization to make organic−inorganic nanocomposite thin films. The initial mixture consists of polycaprolactone (PCL) stabilized gold nanoparticles, reactive monomer alkoxytitanium triacrylate, and photoinitiator benzophenone, dissolved in n-butyl acetate (BuAc) solvent. Upon spin-casting and under UV light, solvent evaporates and triacrylate monomer undergoes polymerization, forming a hybrid film exhibiting complex morphologies on several length scales. In particular, we observe a controlled core−shell microdomain assembly of metal nanoparticles, compatibilizer, and metal-infused photo-cross-linkable acrylate polymer host. The composite film also exhibits high electrical capacitance due to the large effective dielectric constant of the metal nanoparticle-rich “nodules”. We characterize the morphology of the film using both polarized light optical, transmission electron (TEM), and atomic force (AFM) microscopy and propose a theoretical model explaining the formation of macro- and microphase-separated structures. Our results demonstrate a route to engage molecular self-assembly in an organometallic hybrid composite which achieves unexpected and unusual material properties that could be used in the electronics industry.

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