Effect of Additives and Installation Temperatures on Setting Behaviour and Mechanical Properties of Self-flowing Silica Bonded No-cement Castables
Elkem Silicon Materials, Kristiansand/Norway
Volume 8, Issue 3, Pages 75 - 80
Microsilica-gel bonded bauxite based no-cement refractory castables (NCCs) have been produced using two readily available types of dispersants. These are compared to NCC with SioxX-Zero, a purposely- developed product for microsilica-gel bonded no-cement castable systems to control flow properties and set characteristics. Three mixing and curing temperatures were applied: 5, 20 and 35 °C respectively. The results show that the setting-behaviour and mechanical properties strongly varies with the type of dispersant and the curing temperature. However, both the setting-behaviour and strength are less influenced by variation in curing temperature in the castables with SioxX-Zero. Since microsilica-gel bond system contains only a small amount of bound water, the castables can be fired at very high heating rates, once the free water has been removed.
dispersants, curing temperature, temperature dependence, no-cement castable (NCCs), microsilica-gel bond
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