作者：MASAKAZU IIDA;EIZO MAEDA;TSUYOSHI OKAMOTO;

作者单位：

刊名：Journal of the Technical Association of Refractories

ISSN：0285-0028

出版年：2007-01-05

卷：27

期：2

起页：90

止页：95

分类号：TQ175

语种：英文

关键词：Blast furnace;Trough;Metal line;Castable;Oxidization of SiC;Corrosion resistance;Fumed silica;SiO_2 content;

内容简介

An investigation was carried out to evaluate the influence of SiO_2 formed from SiC on the corrosion resistance of castable material at the metal line of a blast furnace main trough. In Al_2O_3-Spinel-SiC-C system castable refractories, the SiO_2 content increases by two different means, i.e. by the addition of fumed silica to the castable material and by oxidation of SiC in the material by CO gas. Deterioration in corrosion resistance is clearly recognized in specimens with added fumed silica. On the other hand, in specimens containing SiO_2 generated from SiC, the deterioration is less than with the silica-added specimens. Microscopic observation of SiC oxidized material reveals traces of liquid phase formation that is explained as the result of reaction among SiO (g) evaporated from SiC, Mg (g) evaporated from spinel and Al_2O_3 in the castable matrix. Since the liquid phase thus formed has high solubility for SiO_2, SiO (g) is easily dissolved into the liquid pool under equilibrium conditions. That is, SiO_2 oxidized from SiC is condensed and exists localized in the material. However, in the case of material with fumed silica added, homogeneously dispersed silica components are observed. It can be concluded that the influence of SiO_2 on corrosion resistance is dependent on SiO_2 component configuration and whether it is localized or evenly dispersed.