Crack propagation in piezoelectric ceramics: Effects of applied electric fields

Abstract

Effect of the electrical boundary condition at the crack face on the mode I energy release rate in piezoelectric ceramics Appl. Phys. Lett. 94, 081902 (2009); 10.1063/1.3088855Double torsion testing and finite element analysis for determining the electric fracture properties of piezoelectric ceramics Influence of temperature on the electromechanical and fatigue behavior of piezoelectric ceramics Crack propagation in a piezoelectric lead-zirconium-titanate ͑PZT͒ material under simultaneous mechanical loading and applied electric fields is studied using the Vickers indentation technique. It is demonstrated experimentally that electric fields can inhibit or enhance crack propagation in piezoelectric materials. Cracks introduced by indentation are observed to propagate less under a positive applied electric field ͑the polarity of the field was the same as that for poling͒, whereas under a negative applied electric field, crack propagation is enhanced. Such an effect is observed to be more profound with increasing electric-field strength and decreasing mechanical loading. Attempts are made to compare these experimental observations with the results of various theoretical analyses. A mechanism for the change in crack propagation behavior of the piezoelectric PZT material under applied electric fields is presented.

Phase-Field Modeling of Fracture in Ferroelectric Materials

“…The Vickers indentation technique is commonly used in determining this anisotropy [75,89,101,112,116,121]. These experimental observations show that the cracking along the poling direction of the material has a shorter length and consequently higher fracture toughness, and that normal to the poling direction has a longer length and lower fracture toughness.…”

“…• Radial cracks perpendicular to the poling direction of the material propagate faster than parallel ones [2,75,89,101,112,116,121].…”

“…• A negative electric field (below the coercive field) enhances the crack propagation perpendicular to the initial polarization in ferroelectrics, while a positive electric field retards it [5,50,95,106,121].…”

“…Experiments on insulating cracks have shown that a positive electric field promotes crack extension perpendicular to the poling axis of the material, whereas a negative electric field retards it [75,101,112,116]. Other tests have indicated an opposite phenomenon, where their results show that a positive applied electric field inhibits crack propagation, whereas crack propagation is enhanced under a negative applied electric field [50,95,106,121]. On the other hand, experiments do not show a clear shielding or weakening effect of the microstructure on insulating cracks oriented parallel to the poling and electric field direction [112,116].…”

Anisotropy of Indentation Cracks Propagation of PZT-5H Ferroelectric Ceramics in Air and Water under Sustained Load

“…However, the crack propagation rate during SCC cannot be measured using the specimen, because the crack growth is unstable process during single-edge notched tensile test. The fracture toughness of ferroelectric ceramics can be measured using the Vickers indentation test and the anisotropy of the fracture toughness of poled specimens can also be investigated by the Vickers indentation test [7][8][9]. Can the Vickers indentation test be utilized to investigate …”