Optimization of binder matrix system at self flowing castable refractories and determination of fracture toughness

The use of the self-flowing castable refractories as kiln material in processes like iron-steel, cement and ceramic production is on the rise. Studies on the binding matrix in these monolithic ceramics have also been the focus of research because of the important effect of the matrix on the thermal shock and corrosion resistance of these materials. Reactive alumina with different particle size distribution, specific surface area and crystal size are the important constitutes of the matrix system.The studies that have been practiced, consist of two steps; in the first step reactive alumina was produced from local raw material gibbsite [Al(OH)3]. This reactive alumina used as binder matrix system in high alumina based castable refractory and optimum conditions was evaluated according to their physical characteristics. In the second step, physical characteristics such as rheological behaviours, bulk density, open porosity and thermal shock resistance, bending and compressive strength and fracture toughness in accordance with ASTM E-399 standard were determined. Finally, KIc values of the refractory samples which was prepared from our reactive alumina were higher than that of commercially available samples.