Study On Preparation Of MnO-ZnO-SiO₂ Crystalline Glaze

Crystalline glaze is a sort of art glaze. Using it to decorate ceramics can make the ceramic products more beautiful. More attention has been paid to the study of willemite glaze Researches on other sorts of crystalline glaze have been seldom reported. In this paper, the preparation of MnO-ZnO-SiO₂ crytalline glaze was studied and the optimizing composition of raw materials was determined. The phase constitution, microstructure and crystallization behavior of MnO-ZnO-SiO₂ crytalline glaze were investigated. Also, the crystallization mechanism was discussed.MnO-ZnO-SiO₂ crytalline glaze was successfully prepared by adding MnCO3 into the raw materials of willemite glaze. Crystals appeared columnar and grew radially.The glaze and crystals presented purple and blue. The optimizing content of MnCO3 is 15%-20%.XRD results showed that the crystal phases in MnO-ZnO-SiO₂ crytalline glaze were Zn₂SiO₄ and Mn₂SiO₄, and these phase grew crossly.Study on preparation of MnO-ZnO-SiO₂ crytalline glaze showed that milling time, thickness of the glaze, melting temperature and crystallization temperature had great influence on the appearance of the glaze.Using fly ash as substitute for clay to prepare crystalline glaze body was also investigated. The results showed that with the increase of fly ash content, the ratio of water absorption and porosity of the body decreased, bulk density, bending strength and compressive strength increased. The bonding between the body and glaze was tight. It indicated that it is completely feasible to use coal gangue as substitute for clay to prepare crystalline glaze ceramic body.