Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
When castable raw materials, especially some of the binder (which is mainly calcium aluminate cement) contact water, ions dissolve into the water and the dissolution rate changes with time, then pH and flowability of the solution change. It has a big influence on the hardening of castables. Accordingly, it is important to deterrnine the characteristics of the solution for understanding the characteristics of the raw materials, and for developing castables. The correlation between the hardening characteristics of castables and the change of zeta potential, pH and electric conductivity of calcium aluminate cement and fine powder raw materials in water was investigated, using a zeta potential meter, based on colloid vibration potential method. Electric conductivity suddenly increases in the first several hundred seconds except for 20 deg C, and this step becomes larger with increasing temperature of hydration. There is not a large change in pH, but it also gradually increases with increasing temperature. The level of zeta potential gradually decreases from 20 deg C to 30 deg C, but it hardly changes from 30 deg C to 35 deg C. It is thought that this behavior is caused by the rapid ion dissolution from calcium aluminate cement, resulting in hydration at the first step and the decomposition of hydrate after that. In addition, the hydration mechanism of calcium aluminate cement changes with termperature.
When castable raw materials, especially some of the binder (which is mainly calcium aluminate cement) contact water, ions dissolve into the water and the dissolution rate changes with time, then pH and flowability of the solution change. It has a big influence on the hardening of castables. Accordingly, it is important to deterrnine the characteristics of the solution for understanding the characteristics of the raw materials, and for developing castables. The correlation between the hardening characteristics of castables and the change of zeta potential, pH and electric conductivity of calcium aluminate cement and fine powder raw materials in water was investigated, using a zeta potential meter, based on colloid vibration potential method. Electric conductivity suddenly increases in the first several hundred seconds except for 20 deg C, and this step becomes larger with increasing temperature of hydration. There is not a large change in pH, but it also gradually increases with increasing temperature. The level of zeta potential gradually decreases from 20 deg C to 30 deg C, but it hardly changes from 30 deg C to 35 deg C. It is thought that this behavior is caused by the rapid ion dissolution from calcium aluminate cement, resulting in hydration at the first step and the decomposition of hydrate after that. In addition, the hydration mechanism of calcium aluminate cement changes with termperature.
Influence of ion dissolution in calcium aluminate cements on the hardening of castables
Einfluß der Auflösung von Ionen verschiedener Calciumaluminatzemente auf das Erhärten von feuerfesten Massen
Taikabutsu Overseas ; 17 ; 89
1997
1 Seite, 1 Bild, 1 Tabelle
Aufsatz (Zeitschrift)
Englisch
Temperatureinfluss , feuerfester Beton , Tonerdebeton , Zement , hydraulischer Zement , feuerfester Zement , ungeformtes Feuerfesterzeugnis , pH-Wert , Erhärten (Zementabbinden) , Löslichkeit , chemische Eigenschaft , Zeta-Potenzial , elektrische Leitfähigkeit , Calciumaluminatbinder , Tonerdezement
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