Effect of Al2O3 and SiO2 Ratio and Temperature Profile on Willemite Crystal Glaze

Abstract

Crystal glaze makes beautiful ceramic surfaces. However, it is difficult to fire crystal glaze so that it has the same beautiful look every time. This is because there are many factors which affect its appearance. The SiO₂ and Al₂O₃ ratio in glaze compositions, firing profiles and the thickness of glazes were varied in this research in order to investigate effects of these factors on crystal glazes. Results showed that glazes with high SiO₂ and Al₂O₃ ratios had small crystals and matt surfaces. Large and dispersed crystals could be obtained in crystal glazes which were fired without T2 firing profile. Finally, crystal glazes which were coated by immersing twice for 3 and 5 seconds were almost identical.