The microstructure and bending strength of aluminous porcelains were analyzed at rising sintering temperatures. It was found that, in the presence of high alumina content, the particle rearrangement process during sintering is inhibited by the formation of a skeleton of alumina particles that are insoluble in the liquid phase. The bending strength increases along with the amount of crystalline phase, with the alumina particles contributing more effectively to this increase than the mullite crystals.
aluminous electrical porcelain; microstructure; bending strength