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以硝酸铬和葡萄糖为原料,按照一定碳含量配比配置混合溶液,烘干后获得前驱体粉末,然后采用碳热还原法制备纳米碳化铬粉末。利用热重-差热分析、X射线衍射、扫描电镜和透射电镜等测试方法对反应过程及产物的物相和形貌进行表征。结果表明:升高配碳量有利于促进碳热还原反应进行,配碳量过低时产物含有贫碳相碳化铬(Cr_7C_3),配碳量过高则会增加产物残碳量,试验最佳配碳量为25.71%;反应温度为1 100℃、保温时间为1 h时,产物为单一的Cr_3C_2,产物粉末由平均粒径为100 nm的椭球形颗粒组成,分散性好,无明显团聚现象。
Using chromium nitrate and glucose as raw materials, the mixed solution is arranged according to a certain carbon content ratio, and the precursor powder is obtained after drying, and then a nano-chromium carbide powder is prepared by a carbothermal reduction method. The reaction process and the phase and morphology of the product were characterized by TG-DTA, X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results show that increasing carbon content is favorable for promoting the carbothermal reduction reaction. When the carbon content is too low, the product contains carbon-poor chromium carbide (Cr_7C_3). If the carbon content is too high, the residual carbon content of the product will increase. The amount of carbon is 25.71%; the reaction temperature is 1 100 ℃, the holding time is 1 h, the product is a single Cr_3C_2, the product powder is composed of ellipsoidal particles with an average particle size of 100 nm, good dispersibility and no obvious agglomeration.