Effects of glucose pretreatment and boric acid content on the synthesizability of B4C ceramics

Abstract

Synthesis of boron carbide (B₄C) as one of the hardest materials on planet Earth is of particular importance due to its wide range of industrial and engineering applications. For this purpose, boric acid and polymers can be used as the boron and carbon sources, respectively. From the family of saccharides in polymeric materials, glucose has shown the best performance for the synthesis of B₄C. In this research, untreated and pretreated (caramelized by heating) glucose precursors were selected and mixed with boric acid for subsequent pyrolysis and synthesis processes. X-ray diffractometry and Fourier transform infrared spectroscopy confirmed that heat-treated glucose is a better carbon precursor for B₄C synthesis. In order to evaluate the effect of the amount of boric acid, more than its stoichiometric ratio, additional amounts of boric acid (10-40%) were also examined and the excess amount of 30% was determined as the optimal value.