CeAlO_(3)在不同w(CaO)/w(Al_(2)O_(3))保护渣中的溶解行为  

Dissolution behavior of CeAlO_(3) in mold fluxes with different w(Ca O)/w(Al_(2)O_(3))

作　　者：郑毅浩 亓捷[1,2] 郑祥 刘承军 姜茂发[1,2] ZHENG Yihao;QI Jie;ZHENG Xiang;LIU Chengjun;JIANG Maofa(Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education),Northeastern University,Shenyang 110819,Liaoning,China;School of Metallurgy,Northeastern University,Shenyang 110819,Liaoning,China)

机构地区：[1]东北大学多金属共生矿生态化冶金教育部重点实验室,辽宁沈阳110819 [2]东北大学冶金学院,辽宁沈阳110819

出　　处：《钢铁研究学报》2023年第9期1092-1099,共8页Journal of Iron and Steel Research

基　　金：国家自然科学基金资助项目(U1908224,51904064);中央高校基本科研业务费专项资金资助项目(N2125013)。

摘　　要：稀土钢连铸过程中,结晶器内上浮至渣金界面的高熔点稀土夹杂物如果不能被保护渣有效的溶解吸收,进入保护渣后会改变渣的理化性能,影响连铸顺行。通过高温实验研究了CeAlO_(3)在连铸保护渣中的溶解机制,探究了保护渣w(CaO)/w(Al_(2)O_(3))(简写为C/A)对溶解过程的影响。实验结果表明,Ce AlO_(3)溶解过程中,夹杂物-渣界面会形成Ce^(3+)和Ca^(2+)的浓度边界层。在C/A为0.8的保护渣中会形成中间产物CaCeAl_(3)O_(7),随着C/A增加到1.0,中间产物Ca Ce Al_(3)O_(7)减少;继续增加C/A至1.2,中间产物消失。其溶解机制为,低C/A渣中AlO_(4)^(5-)较多,在浓度边界层中Ce AOl3溶解形成的Ce^(3+)与渣中Ca^(2+)、Al O45-反应生成中间产物Ca Ce Al_(3)O_(7),然后中间产物再向渣中溶解,溶解方式为间接溶解。高C/A渣中AlO_(4)^(5-)较少,不足以达到固相形核浓度而形成中间产物,Ce AlO_(3)通过离子扩散溶解于渣中。因此,当保护渣C/A低于或等于1,CeAlO_(3)在渣中的溶解方式为间接溶解,当保护渣C/A超过1时,Ce AlO_(3)在渣中的溶解方式转变为直接溶解。During the continuous casting of rare earth steel,the rare earth inclusions with high melting points will float to the slag-steel interface in the mold.If these inclusions cannot be effectively dissolved and absorbed by the mold flux,the physicochemical properties of the slag will be changed and the continuous casting process will be affected consequently.The dissolution mechanism of Ce AlO_(3) in the slag and the effect of w(CaO)/w(Al_(2)O_(3))(abbreviated as C/A)on the dissolution process was investigated through high-temperature experiments.The experimental results show that a concentration boundary layer of Ce^(3+)and Ca^(2+)is formed at the inclusions-slag interface during the dissolution of Ce AlO_(3).The intermediate product Ca Ce Al_(3)O_(7) is formed in the mold flux when C/A is 0.8 and as the C/A ratio increases to 1.0,the intermediate product Ca Ce Al_(3)O_(7) decreases,but when C/Acontinues to increase to 1.2,the intermediate product disappears.The dissolution mechanism is that there are more Al O_(4)^(5-)in low C/A slag,and the Ce^(3+)formed by the dissolution of Ce AlO_(3) in the concentration boundary layer reacts with Ca^(2+)and AlO_(4)^(5-)in the slag to generate the intermediate product Ca Ce Al_(3)O_(7).Then the intermediate product dissolves into the slag again.The dissolution method is indirect dissolution.There is less Al O_4~(5-)in high C/A slag,which is not enough to reach the solid phase nucleation concentration and form the intermediate product,and Ce AlO_(3) is dissolved in the slag by ionic diffusion.Therefore,when the C/A is lower than or equal to 1,the dissolution method of Ce AlO_(3) in the slag is indirect dissolution.The dissolution method of Ce AlO_(3) in the slag changes to direct dissolution when the C/A is more than 1.

关 键 词：CeAlO_(3) 稀土夹杂物 CaO-Al_(2)O_(3)基保护渣 溶解机制 w(CaO)/w(Al_(2)O_(3)) 

分 类 号：TF4[冶金工程—钢铁冶金]