Influence of initial misfit strains on small scale domain switching ahead of interface crack between piezoelectric layer and dielectric isotropic substrate

This study derives the effect of discontinuous initial strain distributions on the small-scale domain switching ahead of the bi-material notch formed between a piezoelectric layer and dielectric isotropic substrate. As a piezoelectric layer the piezoelectric ceramics PZT-5H grown on the elastic substrate formed by amorphous silicon dioxide (SiO 2 ) is considered. The energetic switching principle and micromechanical domain switching framework proposed by Hwang et al. (1995) is applied. The initial thermal misfit constant strain is included in the constitutive relations. The analysis of the asymptotic in-plane field of the bi-material notch is conducted utilizing the extended Lekhnitskii-Eshelby-Stroh formalism. The asymptotic in-plane field is used to predict the domain switching zone applying the energy-based criterion. The influence of the thermal misfit strain on the size and shape of the switching zone in the piezoelectric layer is computed for various initial poling directions.