Mechanical properties of silica fume reinforced epoxy glass microballoons syntactic foams

Abstract

Silica fume, a by-product obtained during the smelting process of silicon and ferrosilicon alloys, is widely used as a filler material in concrete for construction purposes. This study discusses the use of silica fume (1–7% v/v) as novel fillers in epoxy glass microballoon syntactic foams. The total filler loading i.e. glass microballoons and silica fume is maintained at 40% (v/v). Epoxy syntactic foams are popularly being used in the construction industry for the fabrication of light-weight materials in the sandwiched configuration. The use of silica fume is expected to improve the mechanical properties of such syntactic foams, which otherwise suffer due to the incorporation of hollow glass microballoons. As expected, the incorporation of silica fume enhanced the mechanical properties of the base syntactic foam. Epoxy glass microballoons reinforced with silica fume (5% v/v) increased the specific tensile strength by ∼ 47 percent, flexural strength by ∼ 54 percent and compressive toughness by ∼ 23 percent, etc. The increase in properties is attributed to the homogenous dispersion of the silica fume throughout the matrix and the load-bearing ability of silica fume. The use of silica fume opens up vistas in the field of polymer syntactic foams.