Effect of partial substitution of calcium alumino-titanate for bauxite on the microstructure and properties of bauxite-SiC composite refractories
Effect of partial substitution of calcium alumino-titanate for bauxite on the microstructure and properties of bauxite-SiC composite refractories
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DOI：
10.1016/j.ceramint.2017.11.045
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发表时间：
2018-02
影响因子：
5.2
通讯作者：
C. Jianwei;Huizhong Zhao;Han Zhang;Zhen-Gang Li;Jiaqin Zhang
中科院分区：
文献类型：
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作者：
C. Jianwei;Huizhong Zhao;Han Zhang;Zhen-Gang Li;Jiaqin Zhang
铝钛酸钙（CAT）是通过在工业过程中处理钛-铁炉渣获得的，该工业过程涉及熔化、均化、除铁和硅还原。通过X射线衍射（XRD）、扫描电镜（SEM）和热力学分析，研究了CAT加入量与矾土-SiC耐火材料的显微结构、相组成、热机械性能和耐碱性能的关系。结果表明，CAT能与SiO2反应生成钙长石相，使CA 6、CA 2和CaTiO 3相消失。此外，高温下Al 2 O3-TiO 2-CaO-SiO2体系中液相的形成也会使复合材料的性能恶化。随着CAT的加入，复合材料的强度和荷重软化温度降低，抗热震性先增大后减小，当CAT含量≤ 10.8wt%时，复合材料具有良好的耐碱性能。含CAT的矾土-SiC复合材料的耐碱性主要取决于外部致密区。
Calcium alumino-titanate (CAT) is obtained by processing titanium-iron slag in an industrial process that involves melting, homogenization, de-ironing, and silicon reduction. The correlation between CAT addition and the microstructures, phase compositions, thermo-mechanical properties, and alkali resistance of bauxite-SiC refractories were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM), as well as by thermodynamic analysis. The results show that CAT can react with SiO2to form a low-melting-point phase (anorthite), causing the CA6, CA2, and CaTiO3phases to disappear. In addition, the formation of the liquid phase in the Al2O3-TiO2-CaO-SiO2system at high temperatures deteriorates the properties of the composite. The strength and refractoriness under load of the composite decrease with the addition of CAT. Moreover, the thermal shock resistance of the composite first increase and then decrease with the addition of CAT. For CAT concentrations ≤10.8 wt%, the composite demonstrates good alkali resistance. The alkali resistance of the CAT-containing bauxite-SiC composite is mainly dependent on the external dense regions.