Ferroelasticity of the displacive tetragonal phase in Y2O3 partially stabilized ZrO2 (Y-PSZ) single crystals

Abstract

Ferroelasticity of the tetragonal displacive (t′) phase was studied on 4.7 mol% Y2O3 partially stabilized zirconia single crystals. Samples were deformed at 1400 °C at constant strain rate to induce the ferroelastic behavior. Domain reorientation due to the applied stress has been studied as a function of the compression axis and aging time at 1600 °C. Domain switching was found in the as-received and 2-h-aged crystals deformed along the 〈100〉 direction, in which an exceptional high flow stress was reached (>700 MPa). Transmission electron microscopy observations were performed on deformed and undeformed crystals to study the microstructural changes associated with the domain switching. Incremental strain steps on the stress-strain curves and surface texture on the lateral faces of the deformed samples were correlated with the microstructural evidence.