The aging characteristics of 〈001〉-oriented Pb(Zn1/3Nb2/3)O3-PbTiO3(PZN-PT) and Pb(Mg1/3Nb2/3)O3-PbTiO3(PMN-PT) single crystals have been studied under electrical and mechanical drive. A significant increase in hysteretic loss and decrease in piezoelectric constant were observed under continuous excitation. Systematic investigations of piezoelectric aging were then performed using a novel mechanical fatigue method. Piezocrystals were placed between two magnetostrictive plates and clamped. Periodic longitudinal compressive stresses were generated by applying magnetic fields. At both short and long times, the piezoelectric constant was found to decrease slowly. However, in an intermediate range, a pronounced decrease was observed over a narrow time range. The dynamics of aging have been shown to scale to a hierarchical relaxation process, typical of disordered systems such as random field and glassy states.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)