关键词: 琉璃;工艺品;石膏型;精密铸造;气孔缺陷

Abstract: Colored glaze casting is prone to form gas porosity defect,it will affect the appearance,but its forming mechanism and the influencing factors are not completely certain yet.Kiln-formed gypsum mold investment casting method was applied to cast glazed crafts, and magnifying lens, stereo microscope, color photometer, visible spectrophotometer and archimedes principle were used to observe the appearance and study the gas porosity.The results show that the gas porosity defect mainly comes from the gas introduced by the glaze material which can't escape completely.The gas porosity is greatly affected by the raw material size,firing temperature and firing time,when the material size is too small, or the firing temperature is too low, or the firing time is too short, the possibility to form gas porosity defect is high.Once the glazed craft castings suffer gas porosity, their color will become pale, the transparency and density will get reduced, and the more gas porosity, the greater effect on the appearance.Therefore, to solve the gas porosity defect in the colored glaze casting, it needs to comprehensively consider the effects of the material size,firing temperature and firing time.

Key words: colored glaze;craft;gypsum mold;investment casting;gas porosity