超低温高锰钢连铸保护渣研究进展  

Research progress of mold flux for high-Mn cryogenic steel continuous casting

作　　者：王强强 习在辉 何生平[1] 李明 李权辉 WANG Qiangqiang;XI Zaihui;HE Shengping;LI Ming;LI Quanhui(New Materials Institute,College of Materials Science and Engineering,Chongqing University,Chongqing 400044,China;Nanjing Iron and Steel Co.,Ltd.,Nanjing 210035,Jiangsu,China)

机构地区：[1]重庆大学材料科学与工程学院,重庆400044 [2]南京钢铁股份有限公司新材料研究院,江苏南京210035

出　　处：《钢铁》2025年第2期11-22,共12页Iron and Steel

基　　金：极低温清洁能源储罐用特种合金开发与示范应用(2024YFB3713602);国家自然科学基金资助项目(52474346)。

摘　　要：近年来随着钢铁行业节能减排压力的提升,超低温高锰钢生产采用的“转炉/电炉→精炼→连铸”流程工艺具有高效、节能、低成本的优势,成为许多钢铁企业的发展方向。然而,高锰钢由于锰、碳质量分数较高,钢水导热性差,凝固坯壳线膨胀系数大,冷却过程中容易产生较大的热应力,极易产生漏钢风险。加上浇铸过程结晶器钢渣界面不可避免地发生反应[Mn]+(SiO_(2))→[Si]+(MnO),造成熔渣成分和性能改变,恶化保护渣正常的润滑和控制传热功能。前期调研发现国内钢厂采用连铸工艺生产高锰钢均存在不顺行的情况,铸坯容易出现纵裂纹且漏钢事故频发,有的甚至单炉浇铸都非常困难。连铸坯表面缺陷和漏钢事故频发已严重阻碍了超低温高锰钢的规模化生产,保护渣技术作为连铸工艺的关键技术之一,对保障连铸顺行和铸坯表面质量具有重要的影响。当前高锰钢研究主要集中在成分设计、轧制热处理、焊接技术等方面,但是在保护渣专用渣系的研究与开发方面还未见系统报道。为此,着重对含锰钢渣金反应性研究、MnO对熔渣流变特性以及渣膜传热控制影响方面进行相关综述,明确了CaO-SiO_(2)-MnO基低反应性渣系的研究重点。超低温高锰钢低反应性连铸保护渣的开发,对拓展和深化难浇钢种连铸保护渣传热与润滑协调控制理论,以及促进无缺陷铸坯高效、绿色、低碳生产具有重要意义,也是未来专用渣系的发展方向。In recent years,the steel industry has faced increasing pressure to reduce energy consumption and emissions.It has become the development direction of many steel companies to produce high-Mn cryogenic steel by using an efficient,energy-saving,and low-cost"converter/electric furnace→refining→continuous casting"process.However,high-Mn cryogenic steel has a high manganese and carbon content,which results in poor thermal conductivity of the molten steel and a large line expansion coefficient of the solidified slab shell during cooling.This can lead to considerable thermal stresses during cooling,increasing the risk of steel leakage.In addition,the reaction([Mn]+(SiO_(2))→[Si]+(MnO))inevitably occurs at the steel-slag interface in the mold during the casting process,which leads to the change of slag composition and properties,and deteriorates the lubrication and heat transfer control function of mold flux.During the preliminary research,it is found that domestic steel mills using the continuous casting to produce high-Mn cryogenic steel are not running successfully,with the cast slabs prone to longitudinal cracks and frequent steel leakage accidents,some mills even have difficulty in batch cast.The surface defects of the slab and frequent steel leakage accidents have seriously hindered the large-scale production of high-Mn cryogenic steel.As one of the key technologies of continuous casting,mold flux technology has an important influence on ensuring the successful production and the surface quality of slab.At present,the research of high-Mn cryogenic steel mainly focuses on composition design,rolling heat treatment,welding technology and so on.However,there is no systematic report on the research and development of special mold flux system.Therefore,the reactivity of high-Mn steel between slag and steel,the influence of MnO on the rheological characteristics of slag,and the control of heat transfer through the slag film are reviewed,and the research focus of CaO-SiO_(2)-MnO based low reactivity slag system is cl

关 键 词：连铸保护渣 超低温高锰钢 渣金反应 润滑 传热 结晶 微观结构 MNO 

分 类 号：TF777[冶金工程—钢铁冶金]