The effect of sintering conditions on linear shrinkage in porcelainized stoneware tiles as studied in a two-level full factorial experimental design

Linear firing shrinkage, together with water absorption, apparent density and the modulus of rupture, is commonly used as a process control parameter in industrial ceramics. In this paper its optimization is studied with a two-level full factorial experimental design approach. In particular, the influence of forming pressure, sintering temperature and time have been inves-tigated. It has been verified that a Design of Experiment (DOE) approach is a suitable tool to identify the significantfactors that control the densification process of porcelainized stoneware tiles. Moreover a mathematical model has been proposed and tested with good results. The results evidenced that the variable with the higher influence is the sintering temperature followed by forming pressure while time has influence only in sinergy with temperature.