EFFECT OF GREEN STATES ON SINTERING BEHAVIOR AND MICROSTRUCTURAL EVOLUTION OF HIGH-PURITY BARIUM-TITANATE

Compacts prepared from three differently agglomerated powders were studied. Hg‐penetration results and SEM observations were employed to compare the uniformity of powder compacts and to investigate the pore‐size evolution and the microstructural development during sintering. It was found that the more nonuniform the powder compact, the higher the degree of pore growth in the initial and at the beginning of intermediate stages of sintering. Moreover, a higher sintering temperature and a nonuniform microstructure with larger grains could not be avoided. Microstresses might develop because of the differential shrinkage, but they would be released thereafter via the change of grain morphology. It was observed that the aggregate and pore‐boundary separation might not be the primary reason for the initiation of discontinuous grain growth. Copyright © 1990, Wiley Blackwell. All rights reserved