Evolution mechanisms of MgO--Al2O3 in non-oriented silicon steel

被引：0

作者：

Sun, Yan-Hui ^{[1
]}

Zhao, Yong ^{[1
]}

Cai, Kai-Ke ^{[1
]}

Sun, Sai-Yang ^{[1
]}

Ma, Zhi-Fei ^{[1
]}

Fang, Zhong-Qiang ^{[1
]}

机构：

[1] Collaborative Innovation Center of Steel Technology, University of Science and Technology Beijing, Beijing

来源：

Gongcheng Kexue Xuebao/Chinese Journal of Engineering | 2015年 / 37卷 / 01期

关键词：

Calcium treatment; Inclusions; Modification; Silicon steel; Spinels; Steelmaking;

D O I：

10.13374/j.issn2095-9389.2015.01.004

中图分类号：

学科分类号：

摘要：

The evolution mechanisms of MgO-Al2O3 in the process of calcium treatment in non-oriented silicon steel were studied by laboratory experiments, with focus on the evolution process in the early and middle of calcium treatment. A small amount of MgO-Al2O3 surrounded by AlN was occasionally detected besides many pure spinels before calcium treatment. CaS or CaO formed as a transient inclusion in the MgO-Al2O3 surface 1.5 min after calcium treatment. The composition from the inner part to outer part of inclusions was MgO-Al2O3, CaO-MgO-Al2O3 and CaO-Al2O3 in order 4.5 min after calcium treatment. 10 min after calcium treatment, unreacted MgO-Al2O3 spinels disappeared, and simultaneously CaO-MgO-Al2O3 and CaO-Al2O3 inclusions became homogeneous in composition. The phase stability diagrams of Al2O3/MgO-Al2O3/MgO and MgO-Al2O3/xCaO·yAl2O3 were calculated using thermodynamic data. The result showed that it was difficult to modify MgO-Al2O3 spinels with very high aluminum content. In combination with the scanning electron microscopy images, energy-dispersive spectra and element mappings of typical inclusions, the evolution route of an inclusion was described as MgO or Al2O3→MgO-Al2O3→CaO-MgO-Al2O3→CaO-Al2O3, and the alumina content occasionally showed a sudden increase besides a common decrease in the middle part of the product. ©, 2015 All right reserved.

引用

页码：20 / 29

页数：9

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