Production of innovative spinels for refractory materials and improvement of refractory brick properties

In this thesis, innovative spinel materials have been synthesized with the aim of using as an elastifier in MgO based composite refractory materials. These innovative spinel materials exhibit higher corrosion resistance than MgAl2O4 spinel. MAT 5 coded spinel, which has 3.45 gr/cm3 density, was produced at lower sintering temperature Density, strength, modulus of elasticity and hardness of the innovative spinel materials were determined. Physical properties, mechanical properties and thermal shock behavior of different compositions obtained from the additions of 5, 10, 15, 20 and 25 percent by weight (wt %) of MAT 0, MAT 5, MAT 10 and MAT 100 coded spinel materials into the MgO refractories, have been examined. The highest work of fracture was achieved by addition of 15 % (wt.) MAT 5 coded innovative spinel, this value is more than 3,5 times according to pure MgO. MAT 0, MAT 5 and MAT 10 coded spinel materials, which have good refractory properties under high temperatures and low production cost, was produced on industrial scale. MAT 5 and MAT 10 coded spinels have higher corrosion resistance than MgAl2O4 spinel. Refractory bricks were produced by using four different spinel materials, including imported MgAl2O4, MAT 0, MAT 5 and MAT 10 on industrial scale. Physical properties, mechanical properties, thermal shock and corrosion behaviors have been examined. MAT 5 coded spinel has shown similar properties to the imported spinel material, and even shows superior properties in some cases. Bricks, which were produced by using MAT 5 and MAT 10 coded spinel materials showed higher corrosion resistance than others. Keywords: Refractory, MgO, Spinel, Innovative spinel, Mechanical Properties, Thermal Stress / Shock Parameters, Corrosion