Effect of alumina addition on physical and structural properties of ceramic porcelain

Porcelain usually made up from kaolin, feldspar, silica and alumina have a properties as an electrical insulator. The high amount of kaolin addition into the porcelain sample may cause the reduction of sample strength. The effect of adding different amount of alumina into the porcelain composition have revealed the positive possibility in production of ceramic insulator. The different types of raw materials which are feldspar, silica, kaolin and alumina used in production of porcelain insulator sample by varying their composition. The properties of porcelain sample after being sinter at 900 °C was identified according to their physical and structural properties. The porcelain sample properties were investigated using XRD, XRF and density test. The presence of corundum, quartz, albite and mullite phases was believed to increase the physical and structural strength of the porcelain sample. The higher wt. % of alumina resulted in higher value of density, with the lower amount of water absorption and shrinkage. Porcelain sample with 40 wt. % of alumina and 30 wt. % of kaolin content have a low crystallinity of XRD pattern distribution with a density, water absorption and shrinkage of 2.9 g/cm3, 35.9% and 0.62% respectively.