Abstract
Some clay raw materials in Nepal were characterized and their aptitude for porcelain raw material was studied. The main constituent minerals in the samples were identified to be halloysite (7A), mica, quartz, feldspar, and gibbiste by X-ray powder diffraction (XRD), differential thermal analysis (DTA) and transmission electron microscopy (TEM). The chemical composition of the bulk sample showed very low Fe2O3 and TiO2 contents, and therefore, the whiteness of sintered body is on a very good level. The vitrification temperature was around 1200°C and high bulk density still maintained in the temperature range from 1200 to 1350°C, which increased further by grinding the raw materials. Microstructure of the sintered bodies fired at an appropriate temperature showed only small pores homogeneously in the sintered bodies. The samples examined in this study were found to be suitable for raw materials of porcelain.
