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This paper presents the results of structural optimization of a two-spar composite wing for a light aircraft. Different lay-up structures of power components such as spars, ribs and skin panels was considered. The problem of optimization was solved using Pareto optimization method with two criteria: minimal wing weight and minimal wing deflection under aerodynamic load. The angle of ply orientation and power components thicknesses were considered as the optimization parameters. It was shown that the use of the optimized wing from carbon composite could reduce up to 60% of the wing weight comparing with aluminium one. The stress-strain and buckling analysis of the wing and its power components were carried out in FEMAP software package.

In this paper, the weight optimizing of an unmanned aerial vehicle wing spar was designed by using composite material. The optimization parameters were considered, respectively: the wing mass, the location of the spars and ribs, and the spars mass. Determined the selecting of wing spars locations for optimizing spars design based on the minimum weight of the wing. Layer optimizing was used to reduce the weight of composite wing spars. The thickness of front spar and rear spar element such as web and flange were optimized by criterion of allowable normal stress and deflection. The analysis of stress-strain state for all variants were carried out in the FEMAP software package. As the result of analysis, the total weights of composite wing spars reduced 18.17% than the original spars.

Experimental studies of the influence of the heating temperature on the properties of pipe billets made of titanium alloys OT4 and OT4-1 in the formation of parts for the installation of pipeline systems without a protective atmosphere are presented.

The issues of physical modeling of the processes of deforming inhomogeneous materials are extremely relevant in the development of adequate models of technological processes for the processing of materials by pressure. The object of research is the technology of draft of inhomogeneous material in a closed die. The subject of the research is the processes of evolution of the structure of inhomogeneous material during its deformation. The paper presents a technique that allows to fix the dynamics of compaction of a inhomogeneous flat sample in the process of its draft in a closed die at different rates of deformation and contact conditions in the system «sample – matrix – punch». As a result of the experimental study of the process of draft of inhomogeneous material in a closed matrix, the data characterizing the pore formation and distribution of forces depending on the friction factor, the deformation rate and the degree of deformation are obtained. A method of estimating changes in the geometric parameters of pores in the deformation process is proposed, which allows to determine the front of the material compaction. The obtained experimental data can be used to construct a model describing the deformation of an inhomogeneous medium taking into account the compressibility of the material.