Investigation of the parameters affecting the flow characteristics and their effects on the microstructure of alumina based castable refractories

In this thesis, the interactions between additives used in alumina-based castable refractories and their effects on the flow properties and microstructure of alumina-based castable refractory products have been investigated. The influence of additives on the spreading rate, porosity, cold crushing strength properties, and microstructural characteristics of alumina-based castable refractory mortar has been examined. Mortars prepared with different proportions of additives were brought to a castable consistency with a constant water ratio, and spread tests were conducted to identify the effects of the additives. Mold castings were made from the mortars at castable consistency, and after exposure to heat treatment at 110, 800, 1100, and 1300°C, porosity and cold crushing strength tests were performed to determine their effects. Samples heat-treated at the activation temperature of 1100°C for the additives were analyzed through Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) to investigate the effects of the additives on microstructure.