不定形耐火材料由于具有施工方便、整体性好及无需高温烧成等一系列优点而得到广泛应用,鳞片石墨的引入可显著提高耐火材料的热震稳定性和抗渣侵蚀性,但鳞片石墨较差的水润湿性与分散性使其难以直接在浇注料中加以应用,限制了含碳浇注料的发展.石墨表面改性是解决上述问题的有效途径.文章综述了近年来石墨表面改性的研究进展,包括采用溶胶-凝胶法在石墨表面形成二元氧化物(如Al2O3、SiO2、TiO2及ZrO2)涂层或三元复合氧化物(如MgAl2O4、莫来石及铝酸钙等)涂层,通过高温原位反应在石墨表面形成碳化物(如SiC及TiC等)涂层,以及采用合适的表面活性剂来改善鳞片石墨的水润湿性等.分析了表面改性石墨在合碳浇注料中的应用研究状况,对鳞片石墨的表面改性方法、改性层的形成机理及影响因素进行了简要总结,最后从改善表面涂层与石墨基体间的结合方式、降低能耗的先进加热方式及选取高效的表面活性剂等方面对含碳浇注料的未来发展作了展望.%The monolithic refractories have acquired wide application for its convenient installation,good monolithic structure and firing-free character.Thermal shock resistance and slag resistance of refractories can be significantly improved by the incorporation of flake graphite.However,the poor aqueous wettability and dispersibility of flake graphite make it hard to be directly applied to carbon-containing castables.Surface modification of graphite is generally regarded as one of crucial ways to solve these problems.The advances in surface modification of flake graphite are reviewed in this paper,including the formation of binary oxide coatings (e.g.Al2O3,SiO2,TiO2 and ZrO2) or ternary oxide coatings (e.g.MgAl2O4,mullite and calcium aluminate) by sol-gel method,formation of carbide coatings (e.g.SiC and TiC) at high temperature by in-situ reaction method,and improving aqueous wettahility of the graphite by using appropriate surfactants.The effect of modified graphite on the properties of carbon containing castables and the effect of surface modification methods and preparation processing factors on the coating as well as coating formation mechanism are summarized.Moreover,potential research directions of carbon containing castables are also prospected from the perspectives of improving the bonding between coating and graphite,and developing advanced heating technology and efficient surfactants for preparing of surface-modified graphite etc.
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