Reducción de la absorción de agua en tejas vidriadas cerámicas en condiciones de cocción inferiores a 1000 °C de un taller artesanal del sector Racar

Abstract

Glazed tiles made in artisan workshops often have poor water absorption and bending resistance values. These parameters are important as they define the quality of the tile. This research aims to improve the water absorption of glazed ceramic tiles from a craft workshop in the Racar sector at firing temperatures below 1000°C, seeking compliance with the value required in the INEN 990 standard. To this end, the characterization of the raw materials and the paste, the influence of grinding on the plasticity and contraction parameters was studied, and mixtures were formulated by varying the dosage in order to obtain the optimal parameters that allow reducing water absorption. In addition, the glaze firing temperatures of 850°C, 900°C and 950°C were analyzed in order to define an ideal temperature for the production of tiles. The glaze firing temperature that provided the best results was 950°C and the optimal mixture found corresponds to x1=30%; x2=20%; x3=50%; from which curved glazed tiles were obtained that have values of 81.40 kg/cm2

for flexural resistance and 14.19% for water absorption, and

flat glazed tiles with values of 74.90 kg/cm2

for mechanical resistance and 15.22% for water absorption. With this, an improvement was achieved with respect to the values obtained with the artisans' dosage in curved and flat glazed tiles of 20.3% for bending resistance and 19.08% for water absorption (in curved tiles); and 23% for flexural resistance and 16% for water absorption (in flat tiles); which entails an approach to the INEN 990 standard.