Grain growth in the alumina ceramics prepared by different techniques

In this study, we compared the grain growth of the alumina ceramics prepared by hot pressure (HP), hot oscillating pressure (HOP) and dynamic sinter forging (DSF). The results showed that the grain growth rate decreased in the order of HP sample, HOP sample and DSF sample. Analysis of the experimental data using theoretical models revealed that the activation energy was the same for the three samples; and the lower grain growth rate was due to the lower grain boundary energy, which decreased in the same order. The current research showed for the first time that the samples prepared under oscillatory pressure exhibited more stable grain boundaries, which is consistent with the mechanical property measurements reported previously.