摘要
通过对321不锈钢(06Cr18Ni11Ti)浸入式水口结瘤物的扫描电镜(scanning electron microscopy,SEM)观察和能谱(energy disperse spectroscope,EDS)分析,并结合理论计算,探讨了水口结瘤机理.根据成分变化,将浸入式水口试样从外层到内层分别定义为:耐材层、反应层和钢基体层.结果显示,水口结瘤首先是钢液侵蚀水口,形成高熔点渣相,然后钢中Ti N夹杂黏结水口内壁并通过与渣相连接形成链状或网状结构而导致的.对钢中Ti N形成的热力学计算表明温度越高其溶度积越大,对黏结相Ca O-Al2O3-Ti O2-5%MgO的相图分析显示其成分中钙铝比较高,为防止结瘤,要合理控制炉渣成分.
The 06Cr18Ni11Ti( 321) stainless steel has good corrosion resistance and mechanical properties. However,the addition of Ti leads to the formation of TiN inclusions,which deteriorates the condition of continuous casting and causes the clogging. The formation of clogging in the submerged entry nozzle ( SEN) of 321 stainless steel was studied by scanning electron microscopy ( SEM) ,energy disperse spectroscope ( EDS) and thermodynamic calculation. According to the change of components,three layers in sample were defined: the refractory materials layer,the reaction layer and metal layer from the outer layer to the inner layer of SEN. The results show that the molten steel corrodes the refractory materials of SEN and the high-melting-point slag phase forms. Then TiN inclusions attach to the inner layer and form curved chain or reticular structure with slag phase,which causes the clogging of SEN. Results of thermodynamic calculation indicate that the equilibrium solubility of titanium and nitrogen increases with temperature. There is high Ca /Al proportion in CaO--Al2O3--TiO2--5%MgO phase. So controlling the compositions of slag is needed to prevent clogging.
作者
郑建超
潘超
崔崇炜
林平
胡晓军
ZHENG Jian-chao;PAN Chao;CUI Chong-wei;LIN Ping;HU Xiao-jun(State Key Laboratory of Advanced Metallurgy,University of Science and Technology Beijing,Beijing 100083,China;Ruipu Technology Group Co. Ltd. ,Lishui 323903,China)
出处
《工程科学学报》
EI
CSCD
北大核心
2018年第S1期77-84,共8页
Chinese Journal of Engineering
基金
国家自然科学基金资助项目(51474019)
关键词
不锈钢
浸入式水口
结瘤
溶度积
钙处理
stainless steel
submerged entry nozzle
clogging
equilibrium solubility
c alcium treatment
