Solid State Phenomena Vol. 243

Abstract: Orthotropic viscoelastic plates’ connection with made open bolt has been studied. Ends of plates are loaded with constant equally spaced tension. The problem has been solved in three-dimensional statement in the frames of linear theory of viscoelasticity. Solution has been done by the method of quasi constant operators with finite-element realization. The picture of stress state connection evolution at time-constant external load has been obtained. The estimation of connection limiting stress has been done in the frames of A.A.Ilyushin’s limiting stress theory. The possibility of joint immobility disturbance in the course of time has been defined. Unsafe stress as well as the values of constant external action and characteristic time of strength failure occurrence has been determined.

Abstract: The general structure of multilevel models of polycrystalline inelastic deformation based on crystal plasticity and allow describing the evolution of materials internal structure is considered. It is assumed that crystallite inelastic deformation is realized by intragranular dislocation slipping and is accompanied by a lattice rotation. The paper focuses on the description of hardening laws formulated on the basis of physical analysis of defect structure elements interactions. To establish the connection between similar characteristics of different scale levels the consistency conditions of constitutive relations are used. Results of computational experiments on cyclic loading of representative volume of polycrystalline pure copper are obtained; it shows that proposed models allows to describe some effects of metals cyclic loading.

Abstract: The work presents an analysis of the methodical questions of the digital image correlation and acoustic emission application for studying damage accumulation process in composites. The research included tensile mechanical tests on flat samples with a hole. According to the acoustic emission data the localization graphs and the peak amplitude and frequency distributions were plotted. Additionally, the analysis of inhomogeneous deformation fields was made by non-contact three-dimensional digital optical system Vic-3D. The optimal parameters of post processing were selected.