Substitution effect of silica source by amorphous silica on translucency in ternary quartz-feldspar-kaolin system porcelain

Abstract

Translucency and whiteness are valuable characters of porcelain among ceramic products. Highly translucent porcelain is precious and called “translucent porcelain”. Therefore, many efforts have been made on improvement of translucency of porcelain. Ternary system porcelain; quartz-feldspar-clay system, is one of most widely studied porcelains, and the substitution effect of the silica source by amorphous silica from quartz silica is investigated in this study. In this study, the starting composition is 30 mass % silica–40 mass % feldspar–30 mass % kaolin, and quartz silica is substituted by designated amount amorphous silica. The substitution by amorphous silica caused the decrease of maximum density of obtained porcelain. However, the total visible light transmission increased with the increase of amorphous silica substitution. The reason is thought that, the substitution by amorphous silica made highly fluid glass phase at lower temperature and it enhanced the combination of micro pores in the porcelain body. The disappearance of micro pores brings the high translucency of the obtained porcelain.