玻璃陶瓷涂层对轻量莫来石-碳化硅材料抗碱侵蚀性能的影响  

Influence of Glass Ceramic Coating on Alkali Resistance of Lightweight Mullite-SiC Composites

作　　者：刘燕[1] 桑绍柏[1] 武奇 马宇洲 李亚伟[1] 朱天彬[1] LIU Yan;SANG Shaobai;WU Qi;MA Yuzhou;LI Yawei;ZHU Tianbin(Wuhan University of Science and Technology,The State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,National-provincial Joint Engineering Research Center of High Temperature Materials and Lining Technology,Wuhan 430081,China)

机构地区：[1]武汉科技大学,省部共建耐火材料与冶金国家重点实验室,高温材料与炉衬技术国家地方联合工程研究中心,武汉430081

出　　处：《硅酸盐学报》2021年第12期2751-2759,共9页Journal of The Chinese Ceramic Society

基　　金：国家重点研发计划项目(2019YFC1904900);湖北省自然科学基金杰出青年人才项目(2019CFA050)资助。

摘　　要：分别以均化矾土、多孔莫来石和涂覆玻璃陶瓷涂层的多孔莫来石作为骨料制备3种不同的莫来石-碳化硅材料,研究了莫来石-碳化硅材料1500℃热处理后常温物理性能及1000℃模拟钾蒸气侵蚀条件下的结构与性能变化,并借助热力学分析了玻璃陶瓷涂层影响材料抗碱侵蚀性能的机制。结果表明:相比于以均化矾土为骨料制备的传统莫来石-碳化硅材料,通过直接引入多孔莫来石骨料方式得到的轻量莫来石-碳化硅材料耐压强度变化不大,但其抗碱侵蚀性能明显下降;当多孔莫来石骨料表面涂覆玻璃陶瓷涂层后,玻璃陶瓷涂层在高温下形成的液相促进材料烧结,使骨料与基质结合更为紧密,所制得的具有玻璃陶瓷涂层的轻量莫来石-碳化硅材料强度明显增加;并且玻璃陶瓷涂层可以吸收部分钾蒸气并产生液相,进一步保护多孔莫来石骨料免受碱侵蚀,从而使具有玻璃陶瓷涂层的轻量莫来石-碳化硅材料的抗碱侵蚀性能优于传统莫来石-碳化硅材料。Three kinds of mullite-SiC materials were prepared with homogenized bauxite aggregate,porous mullite aggregate and glass ceramic coated porous mullite aggregate,respectively.The physical properties of the mullite-SiC materials sintered at 1 500 ℃were investigated.The structure and properties of the materials after alkali vapor attack at 1 000 ℃ were analyzed.The influence of glass ceramic coating on the alkali vapor attack resistance of material was revealed by thermodynamics analysis.The results show that the strength of the lightweight mullite-SiC material is similar to that of the conventional mullite-SiC materials.However,the lightweight mullite-SiC material has a poor alkali vapor attack resistance.A liquid phase formed in glass ceramic coating at a high temperature promotes sintering,leading to a stronger bonding between aggregates and matrix and an increase in the strength for coated lightweight mullite-SiC materials.Moreover,the glass ceramic coating can absorb a part of K vapor and generate a liquid phase,thus protecting the porous aggregate from alkali vapor.The alkali vapor attack resistance of the lightweight mullite-SiC material is better than that of the conventional mullite-silicon carbide material.

关 键 词：玻璃陶瓷涂层 多孔莫来石骨料 碱侵蚀 莫来石碳化硅 

分 类 号：TQ175.71[化学工程—硅酸盐工业]