RH炉浸渍管用镁铬砖的损毁行为分析

Analyzing the Wear Behavior of Magnesia Chromite Brick(MKB) Used in RH Snorkel

利用化学分析、X射线衍射仪、光学显微镜、扫描电镜及压汞仪等方法对武钢RH精炼炉浸渍管用后镁铬残砖进行了分析,旨在找出镁铬砖的损毁行为。结果表明:残砖粘渣且存有裂纹。残砖渗透、侵蚀层主要有低熔点的钙铝黄长石和铁及其氧化物;在渗透、侵蚀层与原砖层之间存在由FeO和镁铝尖晶石组成的约40μm厚的致密过度层。镁铬砖的损毁主要包括2部分,前期主要是砖体气孔率高、气孔直径大造成的熔渣及钢水渗透,后期是渗透的熔渣及钢水加剧砖体的溶蚀及热剥落;因此改善镁铬砖的气孔特性将会成为减缓其损毁的重要途径。

Used MKB in RH Snorkel of WISCO was analyzed by means of ICP-AES,XRD,optical microscope,SEM and mercury porosimetry,and the aim is to clarify the wear behavior of MKB.The results show that adhering slag and cracks are found in the used MKB.The penetration and corrosion layer are mainly constituted by low-melting point cacoclasite and iron as well as its oxides.There is a dense layer with 40μm thickness formed between the penetration and corrosion layer and initial MKB,which mainly consists of FeO and MgO-Al2O3 spinel.The wear behavior of MKB includes two stages.Firstly,molten slag and steel can easily penetrate the open pores of MKB due to its high apparent porosity and large pore diameter,and then the penetrated slag and steel accelerate the erosion and peeling off of MKB.Thus,improving the porous characteristics will be an important route to decrease or inhibit the wear of MKB.