MgO-Al_2O_3-C材料服役状态下MgO致密层的形成机理  

Formation Mechanisms of MgO Dense Layer in Corrosion Interface of MgO-Al_2O_3-C Refractory in Service State

作　　者：李天清[1,2] 李楠 鄢文[1] 张厚兴[2] 贺中央 刘百宽 

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,武汉430081 [2]濮阳濮耐高温材料(集团)股份有限公司,濮阳457100

出　　处：《硅酸盐通报》2018年第2期666-671,共6页Bulletin of the Chinese Ceramic Society

基　　金：国家自然科学基金(51572203);973计划前期研究专项(2014CB660802)

摘　　要：一种SiC含量为6.0%的MgO-Al_2O_3-C(MAC)材料被用于精炼钢包包壁部位,表现出优异的抗侵蚀性能,对用后MAC材料的物相组成和显微结构进行分析。结果显示,在MAC材料侵蚀界面形成MgO致密层,提高了MAC材料的抗侵蚀性能。MAC材料内的SiC,一方面与MgO反应形成更多的Mg(g);另一方面,SiC氧化后形成的部分SiO_2进入侵蚀层熔渣使熔渣碱度下降,粘度大幅上升,不但提高了MgO在熔渣中的形成速率,而且同时降低了MgO的溶解速率,促进MgO再结晶和MgO致密层的形成。A kind of MgO-Al2O3-C （MAC） refractory with 6.0wt% SiC was tested in the sidewall of the refining ladle, which performed the excellent corrosion resistance, and the phase compositions and the microstruetures of the used MAC refractory were investigated. The results indicate that the formation of MgO dense layer in the corrosion interface of MAC refractory improves the corrosion resistance. The reaction of SiC with MgO continuously accelerates the generating of the Mg （g） in the MAC refractory during the service environment. On the other hand, a part of SiO2 originating from the oxidized SiC entered into the slag of the corrosion interface, which make the basicity of the slag decrease and the viscosity raise, and the recystallization of MgO will be promoted. The two aspects of the SiC synthetically contribute to the formation of the MgO dense layer.

关 键 词：MgO-Al2O3-C材料 MgO致密层 形成机理 SIC 精炼钢包 

分 类 号：TB35[一般工业技术—材料科学与工程]