Effects of magnesium oxychloride and silicon carbide additives on the foaming property during firing for porcelain ceramics and their microstructure

Porcelain green bodies that were prepared with a porcelain tile powder as a major raw material, and magnesium oxychloride (MO) and silicon carbide (SiC) as additives were fired at 1000–1200°C. Effect of the additives on the foaming property for porcelain ceramics and its microstructure was quantitatively investigated to clarify the foaming origin of polished porcelain waste during firing. The experimental results show that a small amount of the mixture of both MO and SiC added into the porcelain green body causes the body foaming during firing more significantly, compared to the addition of either SiC or MO. The foaming of porcelain green body with only SiC is more remarkable than that of the porcelain green body with only MO at the same content and firing conditions. The MO accelerates the foaming of porcelain green body with SiC during firing. In addition, the foaming mechanism was also discussed.