Porcelain is a material produced from kaolinitic clay, quartz and feldspar. Recently, research on new materials such as nonhazardous wastes and natural rocks have been focused on replacing traditional constituents without changing the process or quality of the final products. The aim of this study is to investigate the possibility of the use of volcanic basalt rock in porcelain production. Quartz was progressively replaced by up to 20 wt.% basalt in a traditional porcelain composition. The samples were sintered in an electric furnace with a heating rate of 5 οKminute-1 at 1100, 1150, 1200, 1250 and 1300 οC for 2 h. The effects of this substitution were investigated by measuring the linear shrinkage, bulk density and apparent porosity. The sintered samples were also characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis. The effects of this substitution on sintering and microstructural properties are studied. According to the experimental results linear shrinkage and bulk density values were decreased and the apparent porosity ratios were increased by substitution of quartz by basalt. XRD analysis showed that there are three phases consisting of albite, quartz and mullite at the final basalt containing bodies and mullite peaks were increased by increasing the basalt content. SEM studies revealed that there were unresolved quartz, meta-kaolen and mullite in a glassy matrix.

Keywords: Sintering, Porcelain, Mullite.