Hydration reaction of alkaline refractory castables

 

Alkaline refractory castable usually refers to refractory castable containing magnesia, also known as magnesia refractory castable. In order to meet the requirements of smelting clean steel, reduce slag penetration and improve thermal shock resistance, etc., it can be divided into a variety of products. Common such as magnesium-chromium (MgO-SPINEL) refractories, magnesia-alumina refractories, magnesia alumina refractories, magnesia-alumina titanium refractories and MgO-CaO refractories.

The main component of the alkaline refractory castable is MgO, which easily dissolves calcium ions Ca2? and magnesium ions Mg2 , which will aggregate the highly dispersed high-aluminum fine powder and silicon powder and other active substances, resulting in too fast hardening speed and shortening the usable time , It is difficult to obtain dense construction (casting) body. The solution is to select the best binder to block these cations to control the aggregation rate of the active substance in the dispersed state, so as to obtain a compact construction (casting) body.

Another problem of alkaline refractory castables is that cracks may occur during the drying process, which may damage the construction body (castable). The reason is that MgO hydrates during the drying process. Because the dissolution and precipitation reaction of MgO in water and the direct hydration reaction with water vapor will lead to the structural destruction of the construction body of alkaline refractory castables. As an important measure to improve the anti-hydration performance of alkaline refractory castables, is the right choice of additives (namely the activity of SO? super powder).Another advantage of adding ultrafine powder to an alkaline refractory castable is that it can reduce the infiltration of slag into the alkaline refractory castable.

Wanhao is a manufacturer who is specialized in designing various kinds of furnace and making refractory products for electric furnace, ladle, tundish, blast furnace, AOD furnace, IF furnace, etc.

Article Source:Hydration reaction of alkaline refractory castables

Company name ： Wanhao Refractory

Email:sales100@wanhaorefractory.com

Website: http://www.wanhaorefractory.com/



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