Preparation and Characteristics of tetragonal phase zirconia using dolomite

Abstract

Tetragonal zirconia polycrystal ceramics were stabilized by three different type of dolomite (white, black, cream). The TZP powders were synthesized by co-precipiatation method using ZrOCl2 and 3,4,5,6mol% dolomite solution with HCl .The precipitated gel were washed to give soft agglomerate with higher green density. The powder exhibited the tetragonal phase at 850°C temperature due to their small crystallite size. The phase evolution was the function of calcinations temperature. The densification behaviour shows a higher shrinkage rate for the compacts with white dolomite stabilized. These powders were compacted by uniaxial pressing and fired at 1400 to 1600°C for 4hrs.The relative density was higher for white dolomite stabilized TZP as compared to the other two for all sintering temperature and also it will increasing with temperature. This also retained the metastable tetragonal phase. The observed sintered compacts show an isotropic shrinkage which explains the better density and high hardness and compressive strength (in case of black dolomite) even at higher temperature.