The nature of grain boundaries in alumina fabricated by fast sintering

Fast sintering processes offer promising new routes for the fabrication of bulk ceramics but it is not clear that the microstructural details and properties resulting from a very short, rapid densification procedure are the same in all respects as those resulting from traditional sintering. Here, not fully relaxed grains and their weak mechanical properties of as-prepared nanoscale alumina are described. It was found that low temperature annealing did not cause grain growth but allowed normal boundaries to develop.