中文摘要：

采用燃烧合成–二次还原焙烧法制备CaB6多晶粉末,考察了二次还原焙烧温度和时间对焙烧效果的影响,采用X射线衍射、扫描电子显微镜、透射电子显微镜和激光粒度分析仪对CaB6多晶粉末进行表征。结果表明：Ca3B2O6副产物经二次还原焙烧后转化为CaB6,有利于提高CaB6的产率。随二次还原焙烧温度提高和时间延长,CaB6晶粒逐渐发育完善并长大;焙烧温度过高,产物中Mg3B2O6副产物进一步增多,降低了焙烧效果。合适的还原焙烧条件为：焙烧温度800℃;焙烧时间3～4 h。还原焙烧后得到的CaB6为多晶粉末,纯度大于95.3%。

英文摘要：

CaB6 polycrystalline powders were prepared by combustion synthesis–secondary reduction roasting method.Effects of temperature and time on the resulted products were studied during the secondary reduction roasting process.CaB6 polycrystalline powders were characterized by X-ray diffraction,scanning electron microscope,transmission electron microscope and laser particle size analyzer.Results indicate that the secondary reduction roasting can make the by-product of Ca3B2O6 transfer into CaB6 and heighten the yield of CaB6.CaB6 crystal particles gradually grow up perfectly with increasing the secondary reduction roasting tem-perature and time.If the secondary reduction roasting temperature is too high,the by-product of Mg3B2O6 in the roasted products in-crease,which would deteriorate the roasting beneficial effects to CaB6 products.The optimal roasting conditions follow as that the tem-perature is 800 ℃,and the time is 3–4 h.CaB6 is polycrystalline powder with purity more than 95.3%（in mass） after the reduction roasting.