Effect of Zn Powder for Occurrence of Zinc Ferrite on Transparent Low Firing Glaze Doped with Fe2O3

The effects of 0-15 wt.% Zn metal powder, glost firing temperature, reducing, and oxidizing atmosphere on transparent low firing glaze doped with 5 wt.% Fe2O3 were studied. It was found that the glost firing at 1100°C is suitable for transparent low firing glaze doped with Fe2O3 on earthenware. The color of glazes changed from yellowish brown to dark red-brown with increasing content of the Zn powder which the color intensity of reducing fired glaze is higher than oxidizing one on each same formula. The ZnFe2O4 is main form for both oxidizing and reducing fired glaze. L* a* b* values for fired glazes with 10 wt.% Zn powder and 5 wt% Fe2O3 are 42.2, +8.6, +20.2 and 41.3, +9.9, +20.7 for under oxidizing and reducing atmosphere, respectively. Finally, the water contact angles of the fired glazes are 43.8° and 38.4° under oxidizing and reducing, respectively, which could be easy to cleaning.