Crack Growth in Ferroelectric Ceramics Driven by Cyclic Polarization Switching

Abstract

Ferroelectric ceramics are susceptible to stable crack growth under cyclic electric field of high magnitude. The stresses originate from mismatch strains induced by the electric field around inhomogeneities, such as processing flaws, terminated electrodes and the cracks themselves. The phenomenon is studied using a lead lanthanum zirconate-titanate ceramic. A flaw is indented on the surface of a ceramic sample. Subject to a cyclic electric field of magnitude exceeding the coercive field, cracks eminate from the flaw, in the direction perpendicular to the voltage drop. Tests relevant to the phenomenon are also performed. Polarization and strain as functions of applied electric field are measured at various temperatures and applied stresses. Discharge is demonstrated through an air gap between two ceramic plates subjected to a voltage drop. Models are presented that explain the cyclic nature of the crack growth.

Get full access to this article

View all access options for this article.

References

Anstis, G. R. , P. Chantikul , B. R. Lawn and D. B. Marshall . "A Critical Evaluation of Indentation Techniques for Measuring Fracture Toughness: I. Direct Measurements", J. Am. Ceram. Soc., 64(9):533-538.

Cao, H. C. and A. G. Evans . 1993. "Non-Linear Deformation of Ferroelectric Ceramics", J. Am. Ceram. Soc., 76(4):890-896.

Cao, H. C., M.-Y. He and A. G. Evans. 1993. "Electric Field-Induced Fatigue Crack Growth in Ferroelectric Ceramics", submitted for publication.

Haertling, G. H. 1987. "PLZT Electrooptic Materials and Applications A Review", Ferroelectrics, 75:25-55.

McMeeking, M. R. 1989. "Electrostrictive Stress near Crack-Like Flaws", J. App. Math. Phys., 40:615-627.

McMeeking, M. R. 1990. "A J-Integral for the Analysis of Electrically Induced Mechanical Stress at Cracks in Elastic Dielectrics", Int. J. Engng. Sci., 28:605-613.

Meng, Z. Y. , U. Kumar and L. E. Cross . 1985. "Electrostriction in Lead Lanthanum Zirconate-Titanate Ceramics", J. Am. Ceran. Soc., 68:459-462.

Osborn, J. A. 1945. "Demagnetizing Factors of the General Ellipsoid", Phys. Rew., 67:351-357.

Pak, Y. E. 1990. "Crack Extension Force in a Piezoelectric Material", J.Appl. Mech., 57:647-653.

10.

Sosa, H. A. and Y. E. Pak . 1990. "Three-Dimensional Eigenfunction Analysis of a Crack in a Piezoelectric Material", Int. J. Solids Structures, 26:1-15.

11.

Suo, Z. , C.-M. Kuo , D. M. Barnett and J. R. Willis . 1992. "Fracture Mechanics for Piezoelectric Ceramics", J. Mech. Phys. Solids, 40:739-765.

12.

Suo, Z. 1993. "Models for Breakdown-Resistant Dielectric and Ferroelectric Ceramics", J. Mech. Phys. Solids, 41:1155-1176.

13.

Tada, H. , P. C. Paris and G. R. Irwin . 1985. The Stress Analysis of Cracks Handbook. St. Louis, MO: Del Research

14.

Uchino, K. and A. Furuta . 1992. "Distruction Mechanism of Multilayer Ceramic Actuators", in ONR report on Materials for Advanced Structural Acoustic Control, L. E. Cross , ed., Penn State.

15.

Winzer, S. R. , N. Shankar and A. P. Ritter . 1989. "Designing Cofired Multilayer Electrostrictive Actuators for Reliability", J. Am. Ceram. Soc., 72:2246-2257.