Suzhou Nutpool Materials Technology Co., Ltd

The synthesis of calcium hexaboride (CaB₆) powder via the reaction of calcium carbonate (CaCO₃) with boron carbide (B₄C) and carbon has been investigated systematically in the present study. The influences of heating temperature and holding time on the reaction products have been studied using X‐ray diffractometry, and the morphologies of CaB₆ obtained at various temperatures and holding times have been investigated via scanning electron microscopy. The interaction in the CaCO₃–B₄C–carbon system by which CaB₆ is formed is a solid‐phase process that passes through the transition phases Ca₃B₂O₆ and CaB₂C₂. The optimal conditions for CaB₆ synthesis are a holding time of 2.5 h at a temperature of 1673 K, under vacuum (a pressure of 10⁻² Pa). CaB₆ powder has the same morphology as B₄C, and the properties and the shape of CaB₆ powders can be improved by choosing good‐quality raw materials.