EFFECT OF RADIUS OF RARE-EARTH IONS OF FERROELASTIC DOMAIN SWITCHING OF ZIRCONIA

Pseudo-single crystals of 3 mol% R2O3-ZrO2(R=Yb, Y, Dy, Gd, Eu and Sm) were unidirectionally compressed in the range of 100 to 1000 MPa at 7 00 degrees C to examine the effect of additive cation on ferroelastic domain snitching. The critical stress linearly increased with increasi ng radius of additive cation. The crystal lattice that solutionized la rger additive cation dilated extensively, and was compressed heavily b y adjacent lattices. This lattice compression seemed to prevent domain switching. On the other hand, as the critical stress was proportional to the elastic strain energy stored in the crystal lattice, this impl ies that the activation energy of domain switching increased by the el astic strain energy.