Coupon specimens of poled and depoled lead zirconate titanate (PZT) are examined under combined stress wave and electric loading conditions. Mode‐I crack initiation and fracture behavior is examined using ultrahigh‐speed imaging and two‐dimensional digital image correlation. The dynamic critical stress intensity factor (
Ferroelectric films suffer from both aging and degradation under high ac‐field drive conditions due to loss of polarization with time. In this study, the roles of defect chemistry and internal electric fields on the long‐term stability of the properties of piezoelectric films were explored. For this purpose, lead zirconate titanate (PZT) films with a Zr/Ti ratio of 52/48 doped with Mn‐ (PMZT) or Nb‐ (PNZT) were deposited on Pt coated Si substrates by the sol‐gel method. It was demonstrated that the magnitude of the internal field is much higher in PMZT films compared to PNZT films after poling in the temperature range of 25‐200°C under an electric field of −240 kV/cm. The development of the internal field is thermally activated, with activation energies from 0.5 ± 0.06 to 0.8 ± 0.1 eV in Mn doped films and from 0.8 ± 0.1 to 1.2 ± 0.2 eV in Nb doped films. The different activation energies for imprint suggests that the physical mechanism underlying the evolution of the internal field in PMZT and PNZT films differs; the enhanced internal field upon poling is attributed to (a) alignment of oxygen vacancy—acceptor ion defect dipoles (
- NSF-PAR ID:
- 10459897
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of the American Ceramic Society
- Volume:
- 102
- Issue:
- 9
- ISSN:
- 0002-7820
- Page Range / eLocation ID:
- p. 5328-5341
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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