Study of graphite addition in SiO2-Na2O-CaO vitreous system to produce a foam glass intended for electromagnetic shielding

Abstract

In the present study, we have developed foam glass based on a waste glass of the SiO2-Na2O-CaO vitreous system, using calcium carbonate (CaCO3) which is a natural porogen very abundant in nature, 1% of which ensures the formation of a homogeneous porous structure, formed thanks to its decomposition during sintering process at 800°C. Graphite is introduced into the raw material matrix by substituting 0, 3, 9, and 15 wt% of the waste glass. To analyze the performance of the foam glass obtained, we measured several properties such as density, porosity, coefficient of absorption, reflection, and transmission of electromagnetic waves. The results clearly show that graphite has no remarkable effect on the properties of materials up to 15 wt%. Beyond this, the substitution has a significant effect on density (increasing from 0.225 to 0.64 g/cm3), porosity (decreasing from 91.01 to 73.59 %), and electromagnetic wave Absorption, which improves from 20 % for the sample with 0 wt % graphite (G1) to 91.37 % for the sample with 15 wt % graphite (G2)