EFFECT OF PHASE-SEPARATION ON FERROELASTI C DOMAIN SWITCHING IN 3 MOL-PERCENT-Y2O3-ZRO2

The effect of phase separation on ferroelastic domain switching in 3 m ol%Y2O3-ZrO2 pseudo-single crystals annealed at 1700 degrees C was exa mined. Domain switching occurred in two steps. From TEM analysis, the first step seemed to be the switching of t'-phase, and the second to b e that of t-phase, The effect of phase separation is as follows. First by, the switching amount of t'-phase decreased with decrease of the v olume fraction, whereas that of t-phase increased with increase of the one, Secondly, the critical stress of t'- and t-phase increased with growth of t-phase colony, This is because that the clamping force amon g these phases for domain switching increase, Especially the critical stress of t-phase was strongly effected by the colony size of t-phase.