Prediction of densification during low heating rate sintering of microcrystalline alumina ceramics based on master sintering curve theory

摘要

The master sintering curve (MSC) approach is useful for analysing the shrinkage behaviour of ceramics. In this study, the shrinkage behaviour of alpha-Al_2O_3 of mean particle size 2.5 mu m during constant heating rate sintering was evaluated. An MSC has been constructed using dilatometry data containing lower heating rates only with the help of a combined stage sintering model. The validity of the MSC has been verified from experimental data. A comparison between the predicted and the Archimedes densities showed good agreement, suggesting that it is possible to control shrinkage behaviour during processing using the MSC. The concept of the MSC has been used to evaluate the apparent activation energy for the above powder; a high value of 1148 kJ mol~(-1) was obtained.