Statistical fatigue strength evaluation and inelastic deformation generated during static and cyclic loading in Ce-TZP/alumina nanocomposite: Part 1-in air environment

The statistical fatigue strength evaluations of an intragranular type Ce-TZP/Al2O3 nanocomposite (Ce-TZP/A-N), such as its initial strength, static and cyclic fatigue lives, and its dispersion, were investigated in comparison to 3Y-TZP. The strength degradations during static and cyclic loading of Ce-TZP/A-N were fairly small, and the dispersions of the fatigue life were also quite small compared to those of 3Y-TZP, especially for the case of cyclic loading. In addition, fairly large inelastic deformations (converted strain ≈0.1-0.3%) were observed in the non-failure fatigued specimens after both static and cyclic loading. The amount of inelastic deformations was generally higher under the static loading than under cyclic loading, and increased with increasing the applied stress. In contrast, no inelastic deformation was identified for 3Y-TZP. By means of X-ray diffraction analysis, a good correlation between the amount of inelastic strain and the transformed monoclinic content was recognized for both static and cyclic loading.