Abstract
This investigation aimed at the characterization of monosized ulta high purity Al2O3, observing the microstructural evolution with the measurement of pore elimination during sintering. The small particle size of 0.39μm Al
2O3 powder with a most frequent pore size of 0.12μm in the green stage gave almost full density Al2O3 at the low sintering temperature of 1400°C. Brook's diagram predicted the pore-grain boundary separation, however, no separation was observed. The experimental result of pore elimination agreed with Kingery and Francois' study of pore growth/separation by the parameter of equilibrium dihedral angle. The reduction of the coordination number of grains surrounding a pore is also of importance to obtain high density Al2O3.
