Densification Behavior of Steatite by Two Stage Sintering

Abstract

Structural materials, such as steatite-based ceramic is considered one of the most useful engineering ceramic in place of alumina as a cost-effective way to meet performance requirements. The objective of the research here is to develop a dense body which exhibits good properties as mentioned by the two stage sintering method. Steatite powders used in this work were undoped steatite, steatite doped 20wt% ZnO and steatite doped 20wt% MnO2. The green samples were cold-isostatically pressed and pressureless sintered at temperatures ranging from 950°C to 1200°C at heating rate of 10°C/min through two stage sintering before cooling down to room temperature. The results revealed an improvement in the densification of all the steatites through two stage sintering compared to the conventional sintering. At 1200°C, the steatite bodies with 20 wt% ZnO compositions achieved maximum bulk density of 2.79 g/cm3 which is 10.3% higher than the same steatite doped bodies which exhibited best result when it was conventionally sintered. As a result of bulk density improvement, two stage sintering exhibited outstanding effects in enhancing Young’s modulus and hardness of the steatite body.