抄録
An approximate permanent strain of 0.33% was observed in Ce-TZP/alumina nanocomposite (NanoZR) after static fatigue tests (4-point bending) carried out at room temperature under 865 MPa for 360h. For the deformed specimens, crystal phase transformation, ferroelastic domain orientation, and residual stresses were investigated by using small-area XRD with 2D detector. The monoclinic content of the ground (before testing) and tensile surface (after testing) were 17.2 vol% and 25.4 vol%, respectively. Small amount of crystalline orientation which resulted from ferroelectric domain orientation was observed at both tensile and compressive surfaces. The obtained results revealed that plastic deformation was attributed mainly to volume dilatation involved in t-m transformation on the tensile surface and partially to ferroelastic domain orientation on both surfaces. It was shown that residual stress associated with monoclinic content. Permanent strain and ferroelasticity from 4-point static fatigue test were completely disappeared after annealing at 1100°C. However, residual stress still remained which showed the relationship between the residual stress and monoclinic content in the specimen.
