Effect of particle size distribution on the evolution of porous, microstructural, and dimensional characteristics during sinter-crystallisation of a glass-ceramic glaze

Abstract

Glass-ceramic test pieces, obtained from three different particle size distributions of a frit, were fired at temperatures between 800°C and 1200°C. Evolution of porous characteristics of the test pieces with firing temperature enabled the mechanisms responsible for the microstructural changes and the temperature range in which each mechanism predominated to be identified. Induced anorthoclase and diopside crystallisation porosity was observed to increase, after which it decreased at high temperatures by solution–reprecipitation of these phases, until a minimum was reached. The process caused crystal size, mean pore size, and pore size distribution uniformity to rise. Models were developed that appropriately describe the combined effect of firing temperature and glaze particle mean volume diameter on open porosity, linear shrinkage, mean pore size, and pore size distribution uniformity. Effect of glaze particle size distribution on pore size distribution, in the solution-reprecipitation stage, was perfectly described by mean pore size at solution-reprecipitation onset.