<title>Effect of electrical boundary conditions on domain switching near the crack tip in piezoceramics</title>

Abstract

ABSTRACT A finite element was developed to model the dielectric property of the medium that fills the crack cavity in a piezoelectricmaterial. The element was interfaced with the commercial code ABAQUS which provides the piezoelectric element tomodel the cracked piezoelectric body. The crack cavity permeability effects on the near tip stresses and electric fields in acompact tension specimen were investigated and discussed. The domain switching zones corresponding to various loads andcrack surface electric boundary conditions were obtained. As expected, an increased permeability in the crack cavitydecreased the size of domain switching zone. It was also found that the outcome of domain switching depends on theloading sequence.Keywords: Crack, piezoceramic, permeability, finite element, domain switching 1. INTRODUCTION The piezoelectric crack problem, from a fracture mechanics point of view, was first analyzed by Parton' on a slit crack in apiezoelectric solid, and a permeable electric boundary condition was assumed. This assumption was shown by Suo et al.2 tobe physically unrealistic owing to the potential drop across the lower capacitance crack. Suo et al.2 used the boundaryconditions introduced by Deeg3 and Pak4 that the crack face is free of charge and the crack is impermeable to electric fields