Anelastic behavior of zirconia ceramics under monotonic and cyclic loadings

In this work, an electronic circuit functioning as an elastic-strain subtractor was employed to measure hysteresis loops and time dependent non-linear strain curves of yttria stabilized zirconia (YSZ) ceramics. By analyzing these hysteresis loops and curves under different stress conditions, the authors have found that the zirconia ceramics exhibit strong anelastic behavior (reversible non-linear deformation). This behavior occurs at all stress levels, although the phase transformation certainly does not occur at these lower stress levels. Furthermore, the authors found that the extent of anelasticity depends on the stress level and loading speed. It is assumed that this anelastic behavior is related to grain reorientation or ferroelastic domain switching. If this is the case, it is also expected to contribute to the toughness of zirconia ceramics