Effect of w(CaO)/w(Al2O3) on the Crystallization Properties of CaO-Al2O3-based Mold Flux

被引：1
作者：
Qi J. [1 ,2 ]
Liu C.-J. [1 ,2 ]
Zhang J.-H. [1 ,2 ]
Jiang M.-F. [1 ,2 ]
机构：
[1] Key Laboratory for Ecological Metallurgy of Multimetallic Ores(Ministry of Education), Northeastern University, Shenyang
[2] School of Metallurgy, Northeastern University, Shenyang
来源：
Dongbei Daxue Xuebao/Journal of Northeastern University | 2021年 / 42卷 / 12期
关键词：
CaO-Al[!sub]2[!/sub]O[!sub]3[!/sub]-based mold flux; Crystalline phase; Crystallization temperature; Melt structure; SHTT(single hot thermocouple technique);
D O I：
10.12068/j.issn.1005-3026.2021.12.007
中图分类号：
学科分类号：
摘要：
The crystallization properties of CaO-Al2O3-based mold fluxes with different values of w(CaO)/w(Al2O3) were studied by using single hot thermocouple technique(SHTT) and scanning electron microscope and energy dispersive spectrometer(SEM-EDS). The results showed that the crystalline phases were LiAlO2 and CaO•Al2O3 with a lower w(CaO)/w(Al2O3). They were formed due to the charge compensation of Li+ions and Ca2+ ions to aluminum tetrahedral structure with high polymerization degree. Li+ions were preferentially involved, and LiAlO2 preferentially precipitated. With higher w(CaO)/w(Al2O3), the crystalline phase was transformed into LiAlO2 and 3CaO•Al2O3. The reason for the change was that the relative mass fraction of CaO was increased, accordingly, the degree of polymerization of the mold flux was decreased and 3CaO•Al2O3 was formed and precipitated due to the combination of Ca2+ ions and low-polymerization tetrahedral structural unit Q2. As the w(CaO)/w(Al2O3) was increased from 1.13 to 1.82, the crystallization ability was first weakened and then increased. The crystallization ability was the weakest and the strongest when the w(CaO)/w(Al2O3) was 1.50 and 1.82, respectively. © 2021, Editorial Department of Journal of Northeastern University. All right reserved.
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页码：1717 / 1723
页数：6
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