A PROCESS FOR THE PREPARATION OF BARIUM ZIRCONATE TITANATE CERAMICS

摘要

A process for the preparation of barium zirconate titatnate ceramics comprising the steps of milling of more than 99 % pure BaCO3 68-78 wt%, ZrO2 1-3 wt% preferably 1.5-2.5 wt% and TiO2 25-30 wt% preferably 26-28 wt% with zirconia balls in distilled water at a temperature of 15-40°C for 10 hours, followed by drying the slurry at 75°C; calcinating the powdered mixture of step (a,) at temperature of 800-1300°C preferably at 1000-1200°C for 2-4 hours, followed by remilling in distilled water for 4 hours; palletizing the homogenous calcined mixture of step (b) by air drying and sieving mesh and pressing in a uniaxial press followed by cold isostatic pressing for 10-15 minutes, sintering in a tube furnace with closed ends, in an atmosphere of oxygen at a temperature of 1300-1500°C 2-8 hours preferably 4-6 hour; finishing the pellets of step (d) by grinding, lapping and polishing in a regular size of 1 cm diameter and 0.5 mm thickness.