Effect of MgO-Cr_(2)O_(3) and Mg0-MgAl_(2)0_(4)-based refractories on refractory-steel interface reaction and cleanliness of pipeline steel  

作　　者：Guang-mei Yang Cheng Yuan Chang Liu Qiang Wang Guang-qiang Li Yong-shun Zou Ao Huang 

机构地区：[1]The State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China [2]Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China

出　　处：《Journal of Iron and Steel Research International》2024年第4期849-860,共12页

基　　金：support from the National Natural Science Foundation of China(Grant Nos.U1860205 and 52204352);Youth Project of Hubei Natural Science Foundation(Grant No.2022CFB593);Key R&D Project of Hubei Province(Grant No.2022BAA021);Guiding Project of Scientific Research Plan of Hubei Provincial Department of Education(Grant No.B2022019).

摘　　要：The interaction of MgO-MgAl_(2)O_(4)-based and MgO-Cr_(2)O_(3)-based refractories with X70 molten steel was studied by immersion experiments at 1560℃.The effects of immersion time(30 and 60 min)on the contents of total oxygen(TO),Al,Nb,Si,Mn,and Cr as well as the composition,number density,and size distribution of inclusions in the molten steel were investigated.The influence of the penetration and erosion degree of the molten steel to the refractory on the steel-refractory interface layer was analyzed.The results show that,at 1560℃,the MgO-MgAl_(2)O_(4)-based refractory can better control the contents of TO and the composition of molten steel compared with the MgO-Cr_(2)O_(3)-based refractory.The TO content is only 16×10^(-4) wt.%in the molten steel after reacted with the Mg0-MgAl_(2)O_(4)-based refractory at the end point of refining,4 accounting for 11.5%of that reacted with the MgO-Cr_(2)O_(3)-based refractory(139×10^(-4) wt.%).The number density of inclusions is only 14 mm^(-2),and the average size ofinclusions is only 1.31μm,with thelargest proportion of inclusions in 1-2μm(70%).The Al_(2)O_(3)-MnS-CaO complex inclusions in the original steel changed to complex inclusions dominated by Cr-Nb-Mn-S-O and MgO.Al_(2)O_(3),corresponding to the MgO-Cr_(2)O_(3)-based and MgO-MgAl_(2)O_(4)-based refractories,respectively.The MgO.Al_(2)O_(3) layer was formed at the reaction interface between MgO-MgAl_(2)O_(4)-based refractory and molten steel,which is helpful to restrict the erosion of refractories and the pollution of molten steel.The damage mechanism of the MgO-Cr_(2)O_(3)-based refractory is mainly permeation and chemical reaction,while the damage of the MgO-MgAl_(2)O_(4)-based refractory is mainlyscouring erosion.

关 键 词：MgO-Cr_(2)O_(3)-based refractory MgO-MgAl O_(4)-based refractory Nonmetallic inclusion Erosion interface layer Steel penetration 

分 类 号：TG142[一般工业技术—材料科学与工程]