Low-temperature synthesis of boron carbide powder from condensed boric acid–glycerin product

Abstract

Crystalline boron carbide (B4C) powder was synthesized by the carbothermal reduction of a condensed product formed from boric acid (H3BO3) and glycerin (C3H8O3). The condensed product was prepared by dehydration after directly mixing equimolar amounts of H3BO3 and glycerin, which was followed by pyrolysis in air to obtain a precursor powder from which the excess carbon had been eliminated. The prepared precursor powder had a bicontinuous boron oxide (B2O3)/carbon network structure. Crystalline B4C powder without residual carbon was successfully synthesized from this precursor powder by heating at 1250°C for 5h in an Ar flow.