Structural Changes by Compressive Stresses of 2.0-mol%-Yttria-Stabilized Tetragonal Zirconia Polycrystals

Reorientation of the tetragonal (002) peak in tetragonal ZrO₂ polycrystals (TZP) (so-called domain switching) was studied by XRD and residual stress measurement using TZP specimens containing 2.0 mol% Y₂O₃ that had undergone mechanical and thermal treatments and compressive stress. The observed domain switching was due to a preferred transformation of the tetragonal phase caused by compressive stress above 70 MPa leading to a remnant c-axis orientation normal to the compressive direction. Domain switching did not depend on thermal stress but arose directly from the tetragonal phase with little relation to monoclinic phase.