作者：Eizo MAEDA and Sadao KAKUMA

作者单位：

刊名：Journal of the Technical Association of Refractories, Japan

ISSN：

出版年：2013-06-01

卷：33

期：2

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语种：英文

关键词：low-cement castable. setting mechanism, magnesia powder, polyvalent ions. alumina cement

内容简介

The influence of magnesia powder on the setting of alumina-magnesia low-cement castables was investigated and the setting mechanism of low-cement castables is discussed. The Mg2+ ion concentration in the capillary water increased with a decrease in the grain size of magnesia powder in the castable and the setting was accelerated. Accordingly. Mg2+ ions influenced the coagulation of the colloid. We confirmed our hypothesis that setting can occur in a low-cement type alumina-magnesia caslable containing no alumina cement. In alumina cement-free alumina-magnesia castables the setting was controlled by polyvalent cations such as Mg2+ and Ca2+ dissolved from magnesia powder. Changes in castable characteristics with setting of the alumina cement-free castable were the same as a castable with alumina cement except for the time dependence. Therefore, polyvalent cations but not alumina cement are essential for the setting of low-cement castables. Magnesia powder is a polyvalent ion supplier.