The pressure-assisted master sintering surface

It has been reported that the 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 determine whether the MSC concept is applicable to hot pressing, and to develop the pressure-assisted master sintering surface for alumina. Densification of Sumitomo AKP30 alumina was continuously recorded during heating at 10°C/min at fixed pressures from 7 to 34.5 MPa. Final densities computed from the dilatometer traces were in excellent agreement with values determined by the Archimedes method. The thermocouple was calibrated using the melting point of the Ni/C eutectic. An accuracy of ±2°C was established. 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.