PSI - Issue 42

Jan Sladek et al. / Procedia Structural Integrity 42 (2022) 1584–1590 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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coefficients. Displacements on the upper crack face are only slightly reduced for larger elastic coefficients in domain II, however, on the lower crack surface they are reduced significantly in this case.

Fig. 3 Variation of the induced electric potentials along the crack faces for dissimilar elastic materials: SDC & material2

The induced electric potentials on both crack faces are presented in Fig. 3. The induced potential on the upper crack face is larger than lower crack face. Potentials are larger for bigger flexoelectric coefficients. 4. Conclusions The influence of the flexoelectricity on an interface crack between two dissimilar dielectric layers is investigated numerically. The mixed FEM equations for this problem are developed as the weak formulation of the higher-grade electro-elasticity. The advantage of this approach is that only C 0 continuous elements are sufficient. Displacements and strains approximations are independently applied and constraints between them are satisfied by collocation inside of elements. One can observe in numerical examples that crack opening displacements are reduced for larger values of flexoelectric coefficients. Also the crack opening displacement and the induced electric potential are reduced for larger values of elastic coefficient in lower layer. The flexoelectric coefficient has a strong influence on cracked structures and microelectronic structures are to be analysed with taking into the flexoeletric effect . Acknowledgements The authors acknowledge the support by the Slovak Science and Technology Assistance Agency registered under number APVV-18-0004 and VEGA-2/0061/20.

References

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