Development of glazed earthenware wall tiles through replacement of wollastonite in the body composition

Traditional minerals namely, calcite and dolomite were substituted for the wollastonite in the standard glazed wall tile body composition. Test specimens of three compositions incorporating calcite and dolomite along with a standard composition were fabricated by pressing and firing at three different test temperatures, viz., 1000°, 1050° and 1100°C in an electric furnace. Dry and fired properties of the specimens were determined and compared with those of the standard composition. It was observed that the percent water absorption, fired strength (MOR) and craze resistance of the optimized body composition with complete replacement of wollastonite conformed to the requirements of BIS specification at the test firing temperature of about 1100°C with 2 h dwelling time which was, however, slightly higher by 30° to 40°C than that of the standard wall tile body composition