STUDY ON THE ELECTRICAL-PROPERTIES OF SINGLE GRAIN-BOUNDARIES IN BATIO3 CERAMICS

In the article, the electrical properties of single grains and single grain boundaries in donor doped BaTiO3 ceramics have been investigated . The results show that the grains have no positive temperature coeffi cient of resistance effect (PTCR effect) if the influence of electrode was neglected. The results also show that different grain boundaries have various PTCR effect. The characteristics of current-voltage do no t follow the Heywang model and accord with our modified model. The max imum barrier heights of single grain boundaries are also deduced exper imentally. (C) 1996 American Institute of Physics.