超高功率电炉热区用MgO-C砖的损毁及改进  

Damage and improvement of MgO-C brick used in hot zone of ultra-high power electric furnace

作　　者：赵现华 颜浩 任林[2] 周胜强[1,2] 侯中阳 金钊[1] 张义先 Zhao Xianhua;Yan Hao;Ren Lin;Zhou Shengqiang;Hou Zhongyang;Jin Zhao;Zhang Yixian(Haicheng Lirr Magnesite Materials Co.,Ltd.,Haicheng 114206,China;Beijing Lirr High-temperature Materials Co.,Ltd.,Beijing 102211,China)

机构地区：[1]海城利尔麦格西塔材料有限公司,海城114206 [2]北京利尔高温材料股份有限公司,北京102211

出　　处：《耐火与石灰》2021年第6期40-43,共4页Refractories & Lime

摘　　要：对在超高功率电炉热区使用后的MgO-C砖残砖进行了光学显微镜和扫描电镜分析。熔渣主要沿方镁石晶界侵入,导致镁砂熔损,烧结镁砂由于晶体小、晶界多而蚀损严重。基质和镁砂之间存在裂隙:电熔镁砂和烧结镁砂相比,前者的裂隙大;大颗粒砂和小颗粒砂相比,大颗粒的大;越靠近热面,裂隙越大,导致组织结构疏松,并给熔渣侵入提供通道。渣相和气相使热面基质脱碳,形成脱碳层。热面镁砂颗粒旁的裂隙常与脱碳层贯通,渣侵入脱碳层,镁砂颗粒受冲刷流入渣中,镁砂颗粒越大,这种现象越严重。选择高纯度大结晶电熔镁砂,减小其配料和颗粒极限尺寸,加入高纯石墨,采用优质树脂并添加金属,经高压真空成型,使制品尽量致密低气孔化,这是改进超高功率电炉热区用MgO-C砖的技术途径。The residual Mg O-C brick used in the hot zone of ultra-high power electric furnace is analyzed by optical microscope and scanning electron microscope.The molten slag mainly invades along the crystal boundary of periclase,which leads to the melting loss of magnesia.There are cracks between matrix and magnesia:the cracks of fused magnesia are bigger than that of sintered magnesia;the cracks of big grain sand are bigger than that of small grain sand;the closer the magnesia is to the hot surface,the bigger the crack is,which leads to the loose structure and provides a channel for slag invasion.The slag phase and the gas phase decarbonize the hot surface matrix to form a decarburized layer.The cracks of magnesia particles near the hot surface often run through the decarburized layer,the slag invades the decarburized layer,the magnesia particles are washed into the slag,the larger the magnesia particles,the more serious this phenomenon is.High purity and large crystalline fused magnesia is selected to reduce the ingredient size and maxiumum particle size,high purity graphite is added,high quality resin and metal are added,and the products are made as compact and low porosity as possible by high pressure vacuum forming,it is a technical way to improve Mg O-C bricks used in hot zone of ultra-high power electric furnace.

关 键 词：超高功率电炉 MGO-C砖 脱碳 熔损 

分 类 号：TQ175.713[化学工程—硅酸盐工业]