Publication detail

Application of the gradient theory to interface crack between two dissimilar dielectric materials

SLÁDEK, J. SLÁDEK, V. HRYTSYNA, M. PROFANT, T.

English title

Application of the gradient theory to interface crack between two dissimilar dielectric materials

Type

journal article in Web of Science

Language

en

Original abstract

In the present paper, the interface crack between two dissimilar dielectric materials under a mechanical load is investigated with including flexoelectricity effects. Flexoelectricity is a size dependent electro-mechanical coupling phenomenon, where the electric polarization is induced by a strain gradient in dielectrics. The strain gradients may potentially break the inversion symmetry in centrosymmetric crystals and polarization is observed even in all dielectric mate-rials. The polarization is proportional to the strain gradients in the direct flexoelectricity. Layered composite structures are frequently utilized in microelectronics. Due to a poor adhesion of pro-tection layer and basic material, the interface crack can be created there and for the prediction of failure of these structures it becomes essential to investigate distribution of the interfacial stress and strain fields. Governing equations in the gradient theory contain higher-order derivatives than in the standard continuum mechanics. Therefore, a reliable computational tool is required to solve these boundary-value problems. The mixed finite element method (FEM) is developed, where the standard C0 continuous finite elements are utilized for independent approximations of displacements and strains. The constraints between the displacement gradients and strains are satisfied by collocation at Gaussian integration points inside elements. In numerical examples, a parametric study is performed with respect to flexoelectric and elastic coefficients for both ma-terial regions. The influence of these parameters on the crack opening displacement is discussed.

English abstract

In the present paper, the interface crack between two dissimilar dielectric materials under a mechanical load is investigated with including flexoelectricity effects. Flexoelectricity is a size dependent electro-mechanical coupling phenomenon, where the electric polarization is induced by a strain gradient in dielectrics. The strain gradients may potentially break the inversion symmetry in centrosymmetric crystals and polarization is observed even in all dielectric mate-rials. The polarization is proportional to the strain gradients in the direct flexoelectricity. Layered composite structures are frequently utilized in microelectronics. Due to a poor adhesion of pro-tection layer and basic material, the interface crack can be created there and for the prediction of failure of these structures it becomes essential to investigate distribution of the interfacial stress and strain fields. Governing equations in the gradient theory contain higher-order derivatives than in the standard continuum mechanics. Therefore, a reliable computational tool is required to solve these boundary-value problems. The mixed finite element method (FEM) is developed, where the standard C0 continuous finite elements are utilized for independent approximations of displacements and strains. The constraints between the displacement gradients and strains are satisfied by collocation at Gaussian integration points inside elements. In numerical examples, a parametric study is performed with respect to flexoelectric and elastic coefficients for both ma-terial regions. The influence of these parameters on the crack opening displacement is discussed.

Keywords in English

Direct flexoelectricity; Gradient theory; A pure mechanical load; Induced electric potential

Released

22.10.2022

Publisher

PERGAMON-ELSEVIER SCIENCE LTD

Location

OXFORD

ISSN

0013-7944

Volume

276

Number

B

Pages from–to

108895–108895

Pages count

12

BIBTEX


@article{BUT182420,
  author="Ján {Sládek} and Vladimír {Sládek} and Maryan {Hrytsyna} and Tomáš {Profant},
  title="Application of the gradient theory to interface crack between two dissimilar dielectric materials",
  year="2022",
  volume="276",
  number="B",
  month="October",
  pages="108895--108895",
  publisher="PERGAMON-ELSEVIER SCIENCE LTD",
  address="OXFORD",
  issn="0013-7944"
}