Effect of calcination and sintering temperature on porosity and microstructure of porcelain tiles

Abstract Porcelain tiles are prepared from kaolin, silica sand, feldspar, clay raw materials, and various additives. Ceramic powders are calcined at different temperatures after grinding, drying, and sieving. After the powders are formed and dried, they are sintered at different temperatures. Firing shrinkage (FS), water absorption (WA), and three-point flexure tests of the samples are compared. The mineralogical definitions are completed by performing a phase analysis via X-ray diffraction (XRD). After the microstructural investigations, pore-sizes and distributions are examined by the Barrett–Joyner–Halenda (BJH) method. The powder sintering process increases the crystallization of the compact material. Low porosity and high strength structures are obtained for the samples with powder calcination temperatures of 800 and 900 °C and a compact sintering temperature of 1200 °C. The pore volume increases by increasing the powder calcination temperature in samples compact-sintered at 1200 °C. When the powder calcination temperature of these samples is increased to 1000 °C, the flexural strength decreases. Therefore, the powder sintering temperature of 900 °C is the critical value.