INFLUENCE OF TYPE OF ADHESIVE ON THE INTERFACE DEBONDING OF A BATIO3/EPOXY STRUCTURE UNDER TIME HARMONIC MECHANICAL LOAD AND ELECTRIC FIELD AT ENVIRONMENTAL CONDITIONS

The study deals with investigation of the effect of the used adhesive upon the interface delamination at adhesively bonded piezoelectric patch/layer structure BaTiO3/Epoxy subjected to time harmonic mechanical load and electric field at environmental conditions. This is needed for a predic-tion of conditions, at which these type of structures work safely (without fail-ure). For the interface shear stress in the overlap zone of structure, at two dif-ferent thicknesses of its adherends and three adhesives used, a solution method based on shear lag and Fourier method has been applied. The types of so-lutions obtained depend mainly on the adherends' thickness, the magnitude and frequency of the applied mechanical loading and the shear modulus of the used adhesive. Based on the analysis conducted it has been shown that with increasing magnitude and frequency of applied mechanical load, the delamina-tion length also increased. The delamination could be avoided if the stronger adhesives and thicker adherends are chosen. The debond length is highly de-pendent on the magnitude of electric displacement. The analytical equation for resonant frequencies in the considered structure is developed on the base of obtained solutions and they are calculated at all three investigated adhesives.