钙热还原碳化硼制备硼化钙粉末

The method of calciothermic reduction of B₄C was proposed for preparing CaB₆. The phase transition and morphology evolution during the reaction were investigated in detail. The experimental results reveal that Ca first reacts with B₄C to generate CaB₂C₂ and CaB₆ at a low temperature and that the CaB₂C₂ subsequently reacts with Ca to produce CaB₆ and CaC₂ at a high temperature. After the products were leached to remove the byproduct CaC₂, pure CaB₆ was obtained. The grain size of the prepared CaB₆ was 2–3 μm, whereas its particle size was 4–13 μm; it inherited the particle size of B4C. The residual C content of the product was decreased to 1.03wt% after the first reaction at 1173 K for 4 h and the second reaction at 1623 K for 4 h.

Preparation of CaB6 powder via calciothermic reduction of boron carbide

The method of calciothermic reduction of B4C was proposed for preparing CaB6. The phase transition and morphology evolution during the reaction were investigated in detail. The experimental results reveal that Ca first reacts with B4C to generate CaB2C2 and CaB6 at a low temperature and that the CaB2C2 subsequently reacts with Ca to produce CaB6 and CaC2 at a high temperature. After the products were leached to remove the byproduct CaC2, pure CaB6 was obtained. The grain size of the prepared CaB6 was 2–3 μm, whereas its particle size was 4–13 μm; it inherited the particle size of B4C. The residual C content of the product was decreased to 1.03 wt% after the first reaction at 1173 K for 4 h and the second reaction at 1623 K for 4 h.