GRAIN-BOUNDARY BLOCKING EFFECT IN TETRAGONAL YTTRIA-STABILIZED ZIRCONIA

samples of yttria stabilized tetragonal zirconia, with different grain sizes have been synthesized. Care was taker? to avoid the presence of any trace of monoclinic zirconia. The features of their grain boundar y blocking effect are compared to those of YSZ samples of similar puri ty. Certain variation laws of the blocking effects are quasi identical , especially some dependences on the grain size. The most significant differences concern the variation of the blocking factor with temperat ure and the transition to the so-called intrinsic regime. In tetragona l zirconia, the blocking factor continuously decreases in the temperat ure interval 150-600 degrees C and the onset of the intrinsic regime c ould occur at a smaller grain size of about 0.9 mu m. (C) 1998 Elsevie r Science Limited All rights reserved.