On the fracture toughness of ferroelectric ceramics with electric field applied parallel to the crack front
نویسندگان
چکیده
Mode I steady crack growth is analyzed to determine the toughening due to domain switching in ferroelectric ceramics with electric field applied parallel to the crack front. A multi-axial, electromechanically coupled, incremental constitutive theory is applied to model the material behavior of the ferroelectric ceramic. The constitutive law is then implemented within the finite element method to study steady crack growth. The effects of electric field on the fracture toughness of both initially unpoled and poled materials are investigated. Results for the predicted fracture toughness, remanent strain and remanent polarization distributions, and domain switching zone shapes and sizes are presented. The effects of the plane-strain constraint and transverse stress are also established. Finally, the model predictions are discussed in comparison to recent experimental observations. 2004 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
منابع مشابه
Pii: S1359-6454(97)00123-7
Low fracture toughness of ferroelectric ceramics calls for a reliability concern in the development of smart structures. For ferroelectrics under mechanical and electrical loadings, the intensified stress and electric fields in the vicinity of a crack-like flaw lead to domain reorientation. The switched domains induce incompatible strain near the flaw and consequently change the apparent fractu...
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