الفهرس 
AcknowledgmentOnly 14 pages are availabe for public view
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Abstract
The experimental analysis that has been carried out to investigate the properties of the available raw materials and characterization of the produced alumino-silicate refractory bricks, have all led to evaluate the factors affecting the physico-mechanical and thermal properties of the refractory alumino-silicate brick products.
Obtaining a high quality refractory brick necessitates the use of high quality raw material of suitable grain size. The quality of the alumino-silicate refractory raw material depends upon the ratio of alumina to silica, free silica content and impurities percentage. The physico-mechanical characteristics of the produced refractory brick are controlled by the alumina content, surface area ratio of binder/grog and the porosity and bulk volume. The effective ratio in any mixture of alumino-silicate refractory brick has been determined by investigation the surface area of the materials used. This ratio was found 2:1 in super-duty fireclay brick and 1:1 in high alumina 80% A12O3 bricks.
Attaining high densification and low porosity characteristics of the final product requests the use of the optimum grain size ratio in any batch of alumino-silicate refractory bricks. This was found to be 45-50% coarse, 5-10% medium and 40-45% fine grains. The maximum grain size in any batch was found to be lower than 4 mm. The coarse grain size ranges between 3.962mm and 1.650 mm and can be used as 15-20 % in the total mixture, while 30-35% of the coarse grain ranges between 1.650 mm and 0.589 mm. The medium grain size ranges between 0.589 mm and 0.208 mm, while the fine grain size is less than 0.208 mm.