MgO-Al-C质材料的水化机理及抗水化性能  

Hydration Mechanism and Hydration Resistance of MgO-Al-C Materials

作　　者：樊海兵[1] 李亚伟[1] 桑绍柏[1] 李远兵[1] 赵雷[1] 金胜利[1] 李淑静[1] 

机构地区：[1]武汉科技大学高技术陶瓷与耐火材料国家重点实验室培育基地,武汉430081

出　　处：《硅酸盐学报》2011年第3期430-435,共6页Journal of The Chinese Ceramic Society

基　　金：湖北省科技厅自然科学基金重点项目(2009CDA050)资助

摘　　要：采用X射线衍射仪、扫描电子显微镜、Fourier变换红外光谱仪等研究了MgO-Al-C质材料水化前后的物相组成、微观结构及O—H键强弱的变化,探讨了MgO-Al-C质材料的水化机理。在此基础上,以板状刚玉取代部分电熔镁砂颗粒,以改善MgO-Al-C质材料的抗水化性能。结果表明:MgO-Al-C质材料除因加热过程中Al粉反应形成的AlN和Al4C3发生水化外,材料中MgO及未反应金属Al的水化也不容忽视。MgO水化形成Mg(OH)2,Al、Al4C3和AlN水化形成Al(OH)3并放出气体,反应伴随有体积膨胀,导致MgO-Al-C质材料裂纹的产生和强度下降。刚玉替代部分电熔镁砂颗粒后,材料致密度提高,抗水化性能得到改善。The phase composition,microstructure and O-H stretching of the MgO-Al-C materials before and after hydration were analyzed by X-ray diffractometer,scanning electron microscope and Fourier transform infrared analyzer.The hydration mechanism of MgO-Al-C materials was investigated.The hydration resistance of the MgO-Al-C materials was also investigated via replacing the partially-fused magnesia particles with the tabular corundum aggregate.The results show that,besides the formed AlN and Al4C3 during heating,the hydration of MgO and the unreacted Al can not be neglectable,giving a greater contribution to the hydration of the MgO-Al-C materials.MgO is hydrated to Mg（OH）2,and Al,AlN and Al4C3 are hydrated to Al（OH）3 and some gas products,and the accompanied volume expansion results in the generation of the cracks and the reduction of strength of the MgO-Al-C materials.The densification of the materials increases and hydration resistance is improved after the partially-fused magnesia particles replaced by the tabular corundum aggregate in the MgO-Al-C materials.

关 键 词：氧化镁-铝-碳 抗水化性 红外光谱 热力学分析 机理 

分 类 号：TB333[一般工业技术—材料科学与工程]