الخلاصة:
The purpose of this work is to prepare the triaxial porcelain from native raw materials such as kaolin, feldspar and quartz. The basic porcelain composition of 50 wt% kaolin, 25wt% quartz and 25wt% feldspar. It was prepared by sintering the mixture at different temperatures (1000 -1250°C).The optimum sintering condition gave a bulk density 2.41 g/cm3 and good mechanical proprieties. The tree point flexural strength, Vickers microhardness of porcelain were142 MPa and 6.9 GPa, respectively. The mechanical proprieties of porcelain are improved by addition of Alumina oxide, Fer oxide and Zirconia oxide. The addition of Zirconia oxide improved both mechanical proprieties. The optimum sintering condition gave a higher bulk density 2.55 g/cm3 and good mechanical proprieties. The tree point flexural strength, Vickers micro- hardness of samples containing 8 wt% ZrO2 and sintered at 1200°C were 132 MPa and 13.08 GPa, respectively. These values reveal that the porcelain is a good insulator.
The addition of Fer oxide improved both mechanical proprieties. The optimum sintering condition gave a higher bulk density 2.51 g/cm3 and good mechanical proprieties. The tree point flexural strength, Vickers micro- hardness of samples containing 5 wt% Fe2O3 and sintered at 1200°C were 170MPa and 8.57 GPa, respectively. The addition of Alumina oxide improved both mechanical proprieties. The optimum sintering condition gave a higher bulk density 2.48g/cm3 and excellent mechanical proprieties. The tree point flexural strength, Vickers micro- hardness of samples containing 8 wt% Al2O3 and sintered at 1200°C were 196 MPa and 15.83 GPa, respectively
