Prediction and control of microstructure evolution for sub-microscale α-Al2O3 during low-heating-rate sintering based on the master sintering curve theory

The master sintering curve (MSC) can sometimes be used for analyzing the shrinkage behaviour of ceramics. Densification of α-Al2O3 with the mean particle size of 350 nm was continuously recorded during heating at 0.5, 2 and 5 °C/min. A MSC was successfully constructed using dilatometry data with the help of combined-stage sintering model. The validity of the MSC has been verified by a few experimental runs. The microstructural evolution with densification during different heating-rate sintering was explored. The sintered microstructure is a function of the time–temperature sintering conditions, and it is verified that there exists a link between sintered density and microstructure. The MSC can be used to predict and control microstructure evolution during sintering of α-Al2O3 ceramics.