Abstract
Direct observation methods were successfully applied to investigate the pore structure in green and sintered bodies of alumina ceramics made through a powder granule compaction process. Fracture strength was measured for alumina sintered bodies prepared under three different processing conditions, using granules made through the same procedure. The strength variation among the sintered bodies was quantitatively correlated to the difference in the size and concentration of large pores determined by the observation methods. These pores were developed during sintering.