溶胶凝胶法一步合成ZrB_(2)-SiC-LaB6复合粉体  

One-pot synthesis of ZrB_(2)-SiC-LaB_(6) powders by sol-gel method

作　　者：王传胤 杨伟韬 曾晨 徐平 王亚峰 王啸东 巴开勋 张明瑜[1] 黄启忠[1] WANG Chuan-yin;YANG;Wei-tao;ZENG Chen;XU Ping;WANG Ya-feng;WANG Xiao-dong;BA Kai-xun;ZHANG Ming-yu;HUANG Qi-zhong(National Key Laboratory of Science and Technology for National Defence on High-strength Structural Materials,Central South University,Changsha 410083,China)

机构地区：[1]中南大学粉末冶金国家重点实验室,长沙410083

出　　处：《炭素》2022年第4期15-21,共7页Carbon

摘　　要：采用溶胶凝胶法制备前驱体凝胶,再通过碳热还原法合成了无杂质、粒度小的ZrB_(2)-SiC-LaB_(6)复合粉体。利用FT-IR分析了凝胶化的反应过程,并利用TG-DSC、SEM、XRD和TEM分析手段研究了碳热还原过程。溶胶凝胶法实现了前驱体溶液在分子水平上的混合,能制备粒径小的复合粉体。La离子不仅在凝胶交联网络中起到强的分离作用,减少晶粒间的烧结,而且能降低碳热还原反应的活化能,进而降低烧结的驱动力。非晶态C层包裹在晶粒表面,能够进一步减少表面氧化物杂质和减小粒径。The precursor gel was prepared by sol-gel method, and ZrB_(2)-SiC-LaB_(6) composite powder with no impurities and small particle size was synthesized by carbothermal reduction method. The reaction process of gelation was analyzed by FT-IR, and the carbothermic reduction process was studied by TG-DSC, SEM, XRD and TEM. The sol-gel method realizes the mixing of precursor solutions at the molecular level, and can prepare composite powders with small particle size. La ions not only play a strong separation role in the gel cross-linked network, reducing the sintering effect between grains, but also reduce the activation energy of the carbothermic reduction reaction, thereby reducing the driving force for sintering. The amorphous C layer is wrapped on the surface of the crystal grains, which can further reduce the surface oxide impurities and reduce the particle size.

关 键 词：溶胶凝胶法 ZrB2-SiC-LaB6 凝胶网络 粒径分布 

分 类 号：TB332[一般工业技术—材料科学与工程]