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以ZrO2、H3BO3和C粉为原料,利用碳热还原反应制备ZrB2粉体。通过X射线衍射(XRD)分析粉体物相、扫描电镜(SEM)观察粉体形貌、能谱(EDS)分析粉体成分,并对粉体进行粒度和比表面积分析,研究了B粉、ZrB2晶种、NaCl作为添加剂对ZrB2粉体粒径及形貌的影响。结果表明:添加适量B粉可以提高ZrB2的生成转化率,同时减小颗粒尺寸,得到细小的ZrB2颗粒,当B粉添加量为5wt%时,粉体平均粒径最小,为4.8μm;随着ZrB2晶种含量的增加,ZrB2粉体平均粒径增大、比表面积减小,同时颗粒形貌趋于不规则,联接与团聚现象更加严重,当ZrB2晶种含量达到15wt%时,粉体平均粒径最大,为7.3μm;在NaCl作用下,ZrB2颗粒沿某一方向生长明显,颗粒尺寸显著增大,形貌呈长条状,并且随着NaCl含量增加,颗粒生长得更加粗大,当NaCl含量为15wt%时,粉体平均粒径增大至9.1μm。
Using ZrO2, H3BO3 and C powder as raw materials, ZrB2 powder was prepared by carbothermal reduction reaction. The powder phase was analyzed by X-ray diffraction (XRD), the powder morphology was observed by scanning electron microscopy (SEM), the powder composition was analyzed by EDS, and the particle size and specific surface area were analyzed. Effect of ZrB2 Seeds and NaCl as Additives on Particle Size and Morphology of ZrB2 Powders. The results show that adding appropriate amount of B powder can improve the conversion rate of ZrB2 and meanwhile reduce the size of particles to obtain fine ZrB2 particles. When the content of B powder is 5wt%, the average particle size of powder is the smallest, 4.8μm; The content of ZrB2 seeds increased, the average particle size of ZrB2 powder increased, the specific surface area decreased, and the morphology of particles tended to be irregular. The connection and agglomeration were more serious. When the content of ZrB2 seeds reached 15wt% Under the action of NaCl, ZrB2 particles grow obviously along a certain direction, the particle size is significantly increased, the morphology is elongated, and with the NaCl content increased, the particles grow more coarse, when NaCl When the content is 15% by weight, the average particle size of the powder is increased to 9.1 μm.