Grynevych A. Features of deformation of piecewise homogeneous piezoelements with electrically conducting interface cracks

A problem of determination of the stress-strain state of piezoelectric and piezoelectromagnetic bimaterials with electrically charged electrically conducting crack at the interface of two materials under the influence of mechanical loads, electric and magnetic fields at infinity is considered. The purpose of the work is to develop analytical methods for solving plane problems for electrically conducting electrically charged interface crack with contact zones on its faces in piezoelectric and piezoelectromagnetic bimaterials under the action of mechanical, electrical and magnetic loads. Using the representations of mechanical, electrical and magnetic factors through the piecewise analytic functions and vector functions, the problems are reduced to linear conjugation problems corresponding to the models of open crack and crack with the contact zone and their analytical solutions are found. In closed analytical form all necessary characteristics of the stress-strain state in the vicinity of the crack are obtained. The closed form relations are found for calculating the relative contact zone length, as well as the stress intensity factors, electric and magnetic fields. The influence of external load on the relative contact zone length and the intensity coefficients was studied. In particular, it has been shown that both electric and magnetic fields significantly affect the fracture mechanical parameters of an interface crack in a piezoelectric and piezoelectric / piezomagnetic bimaterials. The results of the dissertation work may be used in the calculation practice of research and design institutions.