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以HfCl4、H3BO3、酚醛树脂为原料,通过溶胶-凝胶结合碳热还原法成功制备了HfB2粉体。分别采用XRD和SEM对高温处理后的粉体相组成和微观形貌进行了分析;采用TGA研究了粉体的高温氧化行为。结果表明:处理温度及硼酸浓度的不同会导致产物纯度、颗粒大小的不同,而且高温氧化性能也有所不同。当处理温度为1800℃且硼酸含量高于生成硼化铪化学计量比时,产物的纯度较高,颗粒均匀,高温氧化性能较好。对溶胶凝胶结合碳热还原法制备HfB2粉体的反应机制进行了探讨。
HfB2 powder was successfully prepared by sol-gel and carbothermal reduction method using HfCl4, H3BO3 and phenolic resin as raw materials. The phase composition and morphology of the powders after high temperature treatment were analyzed by XRD and SEM respectively. The high temperature oxidation behavior of the powders was studied by TGA. The results show that the different treatment temperature and boric acid concentration lead to different product purity and particle size, and high temperature oxidation performance is also different. When the treatment temperature is 1800 ℃ and the content of boric acid is higher than the stoichiometric ratio of hafnium boride, the purity of the product is high, the particles are uniform and the high temperature oxidation performance is better. The reaction mechanism of HfB2 powder prepared by sol-gel combined with carbothermal reduction was discussed.