Effect of alumina characteristics and concentration on thermal behavior, phase evolution, and aesthetic properties of tile glaze coatings

Resumo

In tile manufacturing alumina acts as an opacifier in porcelain tile bodies and as a matting agent in glazes. Calcined alumina is a versatile and a new material for glaze industry due to it’s the densest and more stable crystalline form of alumina. The study was accented on examining of the effect of alumina characteristics and concentration on thermal behavior, phase evolution and optical properties of wall tile glazes. For this purpose several wall tile glazes which contain different phases of alumina and a different concentration were prepared and fired in industrial firing cycle. In the study it was showed that softening and melting temperatures of the wall tile glazes were increased with the increment of the alumina concentration. The crystal phases were detected as anorthite, corundum and gahnite. Depending on the forming of new crystalline phases, glazes with different aesthetic properties were obtained in the study.