Study On The Preparation And Properties Of The Fly Ash-Red Mud Glass-ceramic

In this paper, the fly ash and red mud were used as the main raw material for the preparation of glass ceramic. The good performance of the glass ceramic products are obtained by optimize the raw material ratio and treatment process.The glass ceramics is prepared by using melting method. Five basic glass samples were prepared by adding45%,50%,55%,60%and65%red mud respectively while keeping the total content of fly ash and red mud90%unchanged. The heating treatment temperature was determined as730℃,780℃,830℃,880℃and930℃by the differential thermal analysis of above five basic glass samples, respectively and the five glass ceramics were prepared by heating treatment. SEM and XRD were utilized to study the micro-structure and physical phase of the five glass ceramics. The effect of heating treatment processing on the properties of the glass ceramics was explored. The optimum ratio of the fly ash and the red mud as well as the optimum heating treatment processing was determined.The experimental results show that the crystal phase of glass ceramics composition does not change with the increase of the heat treatment temperature. When the red mud content was at45%, the main crystal phase is nepheline; When the red mud content was at50%, the main crystal phase are nepheline and diopside; When the red mud content were at55%and60%, the main crystal phase are nepheline and mullite; When the content of red mud was up to65%, the main crystal phase was changed to the composite phase of hematite, nepheline and mullite.When the heating treatment is830℃, the bending strength and vickers hardness of the five glass ceramics sample are all very good. Especially, when red mud content is55%, the bending strength of glass ceramics sample prepared is high to190.65MPa; when the red mud content is45%, the vickers hardness of sample prepared is high to730MPa. With the rise of heat treatment temperature, the density of the glass ceramics increases firstly due to the decrease of glass phase, and then its density declines gradually due to the inner defects caused by extra-high heat treatment temperature. When red mud content is55%, the density of the sample prepared is the highest,3.27g/cm3...