(1.昆明理工大学 真空冶金国家工程实验室，材料与冶金工程学院，昆明 650093；2. 东北大学 材料冶金学院，沈阳 110004)
摘 要: 以B2O3为原料，Mg粉为还原剂，通过自蔓延镁热还原反应获得还原产物，经过对还原产物的盐酸溶浸后，制备出超微细无定形硼粉。研究镁热还原工艺对产物的影响，利用激光粒度分析仪测定无定形硼粉的粒径，用静态表面吸附仪测定77.3 K下硼粉的氮吸附等温曲线，通过XRD和SEM分别对还原产物和无定形硼粉的物相及形貌进行分析。结果表明：在B2O3-Mg体系中，影响硼粉纯度的杂质主要是反应过程中生成的酸不溶物MgBx、BxO、Mg2SiO4、FeBx及较难溶物xMgO∙B2O3等，在镁热还原过程中应尽量抑制该类化合物的生成。通过优化制备工艺，在w(B2O3)/w(Mg)为3.0的条件下，制备出硼含量为94.6%、比表面积8.2 m2/g、等效粒径0.36 μm的形貌不规则的超微细硼粉。
关键字: 无定形硼粉；超微细；镁热还原法；比表面积；富燃料推进剂
（1. Science and Technology State Key Laboratory of Vacuum Metallurgy,Faculty of Materials and Metallurgical Engineering, Kunming University ofTechnology, Kunming 650093, China;2. School of Materials and Metallurgy, Northeastern University,Shenyang 110004, China）
Abstract:B2O3 and Mg powders were used as raw materials and reductant respectively. The reductive products were prepared by the magnesiothermic reaction. The boron powders were obtained after the reductive products were leached by HCl. The effects of reductive techniques on products were systematically studied. The particle sizes of boron powders were measured by laser particle analyzer and static volumetric absorption analyzer at 77.3 K. The phases and morphology of the reductive products and boron powders were characterized by XRD and SEM. The results show that the main effects on the purity of boron powders are the insoluble matter MgBx, BxO, Mg2SiO4, FeBx and xMgO∙B2O3. So these compounds must be effectively restrained in the process of magnesiothermic reduction. The irregular ultra-fine amorphous boron powder with purity of 94.6%, specific surface area of 8.2 m2/g and equivalent particle size of 0.36 μm can be gotten when w(B2O3)/w(Mg) (ratio of mass fraction) is 3.0.
Key words: amorphous boron powder; ultra-fine; magnesiothermic reduction; specific surface area; fuel-rich propellant
