EFFECTS OF TITANIA AND SINTERING TEMPERATURE ON THE PHASE DEVELOPMENT AND PROPERTIES OF SINTERED MULLITECARBON COMPOSITE SYNTHESIZED FROM OKPELLA KAOLIN

Abstract

The effects of the addition of titania and sintering temperatures on the phases developed, physical and mechanical properties of sintered ceramic composite produced from kaolin and spent graphite electrode was investigated. The kaolin and graphite of known mineralogical composition were thoroughly blended with 2 and 4 (vol.) % titania. From the homogeneous mixture of kaolin, graphite and titania, standard samples were prepared via uniaxial compaction. The test samples produced were subjected to firing (sintering) at 1300˚C, 1400˚C and 1500˚C. The sintered samples were characterized for the developed phases using x‐ray diffractometry analysis, microstructural morphology using ultra‐high resolution field emission scanning electron microscope (UHRFEGSEM) various physical and mechanical properties were determined. It was observed that microstructural morphology of the samples revealed the evolution of mullite, cristobalite and microcline. The mineralogical phase of the samples revealed the increments in the evolution of mullite and also the variation in other phase attained as the sintering temperature was raised from 1300˚C to 1500˚C for the sample having the same composition. It was concluded that the optimum mechanical property of the ceramic samples produced was achieved with sample that contain 4 (vol.) % titania and sintered at 1300˚C.