DESIGN OF ZIRCONIA GRAIN-BOUNDARIES - AN EXPLORATION OF THE DESIGN OFOXIDE CERAMIC GRAIN-BOUNDARIES

The grain-boundary resistance of ZrO2 mainly consists of the contribut ion from the space-charge layers R(sc) and that from the grain-boundar y phase R(gbp). The reduction of R(sc) can be realized by the segregat ions of solutes with positive effective charge in the space-charge lay er;, while the reduction of R(gbp), an be achieved by deceasing the am ount of the grain-boundary phase, changing the morphology of the phase and forming grain-boundary phase with high conductivity. The best gra in-boundary design effect can only be achieved by the joint design of the space-charge layers and the grain-boundary phase.