Zircon bonded with Iraqi Kaolin

Abstract

Clay is one of many types of raw materials that have plasticity and advantage of securing so used as abinder in refractory products. Iraqi white kaolin used as a binding material in ratio (15, 20, 25, 30)%. Thesamples were formed by dry pressing and left at room temperature for (24)hr then fired at (1200)˚C withsocking time for (2)hr. The Study included Linear shrinkage, Apparent density, Porosity, water absorption,loss in mass, wettability and microstructure by (SEM) as physical properties, Thermal conductivity, andthermal shock resistance as thermal properties. The microstructure of the refractories consist of zirconiumsilicate, mullite phase, and glass binding phase. The refractory showed medium porosity. Increasing ofIraqi white kaolin percentage leads to Increasing the Linear shrinkage ratio, Apparent density, loss inmass and thermal conductivity and decreasing the Apparent Porosity and water absorption ratio , becauseof the Increasing of the liquid phase ratio in refractory. The effect of thermal shock on diametrical strengthstudied, where it is noticed the thermal shock temperatures between (400-600)˚C.