Crack Propagation in PZT.
Abstract
Subcritical crack propagation in the transducer ceramic, PZT, has been studied using the double torsion technique. The effects of testing environment and temperature, as well as the state of poling in the material, have been characterized in detail. Tests run in water and in environments inert with respect to water such as toluene, mineral oil and Freon, a corona supperssant, have established that water enhances slow crack propagation in PZT. Fracture has also been found to depend sensitively on the state of poling. Crack propagation is hindered if poling is perpendicular to the crack plane but is hardly affected if the material is poled parallel to the crack. These results can be explained more in terms of the residual stresses introduced by poling than in terms of the microstructural (i.e., domain structure) changes accompanying poling. A thermal activation analysis carried out on crack propagation data measured in water on unpoled PZT yielded a stress free activation energy of 100 kcal/mol. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1977
- Accession Number
- ADA044399
Entities
People
- B. G. Koepke
- J. G. Bruce
Organizations
- Honeywell International, Inc.