Microstructural evolution based on the pressure-assisted master sintering surface

Master sintering curve (MSC), in which the sintered density is a unique function of the integral of a temperature function over time, is insensitive to the heating path. The present research was undertaken to explore microstructural evolution with densification of alumina during hot pressing, and to develop the pressure-assisted master sintering surface for alumina. Densification of alumina was continuously recorded during heating at 10 °C/min at fixed pressures from 6.9 to 34.5 MPa. Significant grain growth occurred with increasing pressure. The pressure-assisted master sintering surface was successfully constructed. Using this surface, the final density can be predicted to about 1% accuracy for a fixed pressure and an arbitrary temperature–time path.