Main Research Results & Achievements

• A mathematical model of the correlation between macro- and microstructures of nanocomposites is formulated on the basis of hereditary representations that lead to the construction of the defining relation in the form of Volterra integral equation of the second kind. A technique for obtaining optimal parameters of the heredity kernel of the determining equation is developed.
• The elastic properties of a new nanostructured material - single crystals of zirconia are investigated and recommendations for improving the manufacturing technology are given.
• A mathematical model of the impregnation of reinforcing filler under vacuum infusion is constructed. The formulation of the problem of determining the stress-strain state (VAT) in the product in the process of vacuum infusion is formulated.
• The analysis of the design methodology of assembly technological processes is carried out.
• A methodology for presenting the assembly unit in a modular design is developed.
• A technique for constructing an assembly process is developed by the method of linking parts from modules to the process of joining parts.
• The dependence of the electro-plastic effect on the grain size is obtained. As the grain size decreases, the electro-plastic effect decreases and even disappears in the nanostructured state.
• Photonic crystals of gold and silver, as well as other substances based on artificial nanostructured opals, have been created and investigated with the aim of developing new types of sensors, super-sensors and light transmitters in quasi-monochromatic light and acoustic emission.
• The technique of an estimation of a mode of work of a frictional pair of a disk brake in a high-speed railway rolling stock at a design and designing stage is developed. The technique of model tests for frictional heat resistance and heat impulse friction of friction pairs of a disk brake is developed to select the optimum materials for the disc and pads (linings).
• Methods for identifying mechanical properties and constructing the determining relationships of layered polymer composites have been developed. Criteria for the long-term destruction of composites and elements from them have been developed.
• The effect of natural aging on fatigue resistance characteristics of structural steel has been studied.
• Basing on the experimentally established characteristics of the structure and mechanical properties of structural materials, the fundamental nature of the mesoscopic level in ensuring reliable and safe operation of the friction units is substantiated. The models of self-organization of the structure in the surface layers are developed at the contact interaction of structural materials, ensuring their high wear resistance.
• On the basis of the analysis of the deformation characteristics of structural steels, it is established that the nature of the deformation of the material (hardening, softening and cyclic stabilization) can be determined (predicted) by the curves of static loading (deformation) of the material from the ratio of the uniform deformation (to the load to the ultimate strength) Deformation of a single failure, which determines the carrying capacity of the material.
• At the stage of development of the crack, the nature of deformation of the material at its apex also repeats the behavior of the material under static loading, which depends on its structural state.
• Based on the data of structural studies of the level of defectiveness and structural stresses in structural materials and coatings obtained under non-equilibrium conditions, a microstructural model has been developed that explains the nature of the processes of surface destruction (wear) during contact interaction in coatings. The possibility of its use for describing the destruction of both bulk materials and coatings (including nanostructured ones) is investigated.
• The principles of calculation of the contact load in high-quality hermetic riveted joints at all stages of the life cycle of aircraft structures are developed. Analytical solutions of problems on forming a tight riveted connection on the basis of a model of a flat deformed state and solving problems of loading a panel with a rivet for tension, compression, or shear with the introduction of a special stress function are obtained. The solutions are generalized to the case of breaking a hole under cyclic loading. As a result, the criteria for the beginning of depressurization of tight riveted joints have been determined, dangerous levels of external loads have been calculated.
• A complex of analytical solutions of structural and contact problems is obtained, taking into account the deformability of a rough contact for flange connections on the basis of the theory of the Biceno-Grammel rings, taking into account constructive, technological and operational factors. Two methods for calculating the permeability coefficient for a metal-metal contact, as well as nonmetallic compaction with a rigid interfacing surface, are proposed for a probabilistic description of the distribution of material along the height of micro-roughness.
• A unified criterion of cyclic destruction at the stages of formation and development of cracks was developed.
• A method for estimating longevity under cyclic two-frequency loading is developed;
• The method of X-ray diffractometric analysis of the characteristics of the structure of crystalline, amorphous and nanostructured films, coatings, modified surface layers and nanocomposites is based on the restoration of the true value of the scattering intensity by the material under study;
• The test equipment and measuring means for carrying out program non-stationary loading under high-temperature heating in conditions of room temperature and vacuum are developed;
• The concept of dispersed fissuring at cyclic loading of structural materials is developed.