About the possibility of creation of sealed strong structures of rocket and space equipment FDM printing methods

The work shows the possibility of manufacturing products for rocket and space technology using the additive FDM-printing technology. The object of research is the nozzle plugs of the "membrane" type. Taking into account the specific-strength properties of the product during its operation during operation, as well as the features of the FDM-process, the design was optimized, the regularities of the formation of its properties were established. An impregnation technology has been developed to seal the product. The equipment was designed and pneumatic tests were carried out. The properties of materials were investigated taking into account their guaranteed shelf life for 12 years of operation under accelerated climatic tests. It is shown that the production of products by FDM-printing methods is promising and expedient, since the properties being formed are predictable, achievable and stable.

The use of laser radiation to increase the efficiency of nitriding processes

In this study, the technology of laser processing is tested. This combined process of laser chemical-thermal treatment allows by modifying the structures of the surface layers of metal alloys to significantly increase the thickness range of high-quality nitrided layers with a radical reduction in time and energy consumption of the process, significantly expand their applications to increase wear resistance, corrosion resistance and other performance characteristics.

TO THE QUESTION OF ANALYSIS OF EQUATIONS OF MOTION OF A RIGID BODY DURING THE MECHANICAL OSCILATIONS

Depending on the current position of the mass in different areas of the spring deformation during the oscillation process the values that determines the natural frequency of free continuous oscillations have opposite signs. It is defined by the change in the direction of acceleration of the mass in these areas, which makes it possible to determine a single inhomogeneous differential equation of the oscillation process in different areas of the movement of the mass. When the oscillation amplitude is much less than the static position of the mass, this inhomogeneous differential equation represents a homogeneous differential equation of free undamped oscillations.

Axial tension of nonlinear elastic composite shells of zero Gaussian curvature with a rectangular hole

The formulation of physically nonlinear problems for composite shells of zero Gaussian curvature weakened by a rectangular hole under the action of axial loading is given. The initial equations are the equations of the theory of non-sloping shells, in which the Kirchhoff–Love hypotheses take place. Geometric relationships are written in vector form, and physical relationships are based on the deformation theory of plasticity for anisotropic materials. The system of resolving equations is obtained from the Lagrange variational principle. A technique has been developed for the numerical solution of two-dimensional physically nonlinear problems for orthotropic composite shells of this type, based on the use of the method of additional stresses and the method of finite elements. A variant of the finite element method is proposed, the peculiarity of which lies in the vector approximation of the sought values and the discrete execution of the geometric part of the Kirchhoff–Love hypotheses (at the nodes of finite elements). Using the developed technique, the nonlinear elastic state of an organoplastic conical shell with a rectangular hole, which at the ends is reinforced with frames and loaded with uniformly distributed tensile forces, has been investigated.

Ways to eliminate inflections in teaching disciplines of intellectual property

The history of introduction of disciplines devoted to the methodology of scientific and technical creativity, acquisition, protection, protection and commercialization of intellectual property rights in the Kyiv Polytechnic Institute (KPI) is presented chronologically. The positive and negative consequences of teaching disciplines in intellectual property and patent science are analyzed. Emphasis was placed on a strategic mistake when two disciplines (one legal, the other integrated engineering creative direction) merged into one and two teachers of two different departments of KPI began to teach.

Implementation of the specialty "Materials Science" at Kherson National Technical University as an integrated educational and scientific program in the field of mechanical engineering

Kherson National University of Technology has introduced an educational and scientific program. Scientific program for the specialty of material sciences and accumulated experience in its provision, taking into account the peculiarities of educational sphere "Mechanical Engineering", educational activity at the previous levels of education (bachelor's degree, master's degree), the requirements of Ukrainian industry and the region in particular. The educational and scientific programs of educational and scientific institutions of Ukraine are analyzed according to their scope, subject area, teaching methods, tools and equipment used. The structure of general and personal competencies and their corresponding program learning outcomes with the necessary educational components of the normative and selective parts are given. It is shown how the value of this or that component is reevaluated by the maintenance group and the external influence on their content by stakeholders of different levels. It is noted that the subject area of educational and scientific programs of the specialty of material sciences covers several areas of different branches of education, which makes it possible to expand its scope to the study of unique phenomena, traditionally do not involve purely structural studies of materials and goods.

Rating of the limiting state of 20K steel under low-cycle loading using the using the method of LM-hardness

In the express diagnostics of the condition of the material of the elements of the structures in operation and the materials for the manufacture of the responsible elements of the equipment, it is necessary to take into account the current damage. At the same time, non-destructive methods of control are more relevant, which allow to assess the level of scattered damage in the material and the degree of degradation of its structure of the metal. Another important factor in controlling the current state of the material is the assessment of the residual life of the structural element under operating loads. This paper presents the results of research on the application of the non-destructive method of LM-hardness in assessing the characteristics of the limiting state of the material of real structural elements operating under low-cycle load.

Predicting the effect of bullets, shrapnel, explosions and other shock loads on military mobile robots

The factors that influence the probability of failure-free robots of mobile robots for military purposes are determined when they are hit by bullets, fragments, explosions and other shock loads. It has been established that the areas of greatest danger for special-purpose mobile robots are the barrel group, actuators, guidance system, ammunition stores, etc. On this basis, recommendations have been developed to improve the survivability of military mobile robots.

Calculation of elements of machine-building structures on vibration strength

A method and an automated system for calculating structural elements for vibration strength have been developed. The calculation algorithms are based on a new method of forming Rayleigh-type functionals and minimizing them by the coordinate descent method. The use of the coordinate descent method avoids the problems associated with the formation, storage and operation of global matrices of stiffness and mass. This makes it possible to solve large-scale problems using only the operational memory of the PC. The developed approach allows to solve problems on own and forced fluctuations. The software is formed on a modular basis, which allows you to improve and expand this package of applications. The software has been tested on a large number of test and application tasks. The proposed calculation method and the developed automated system were implemented in engineering practice.

Higher Education in The Republic of Serbia from the perspective of the European Educational Area

Process of accession of Higher Education Institutions (HEIs) in Serbia to the Bologna Process was requiring realistic solution while concurrently was nurturing both the existing national education system and appreciation of oversea. After fifteen years of EHEA, still there have been significant differences between national and European education. Implementation of European experiences and harmonization of national with the European Education requires dealing with many issues both at the state level and at the level of Universities and Faculties. In the paper it is presented an analysis of the situation of HEIs in Serbia in comparison with the EHEA in terms of the number of students, the number of HEIs, teaching staff, allocations (costs) per student and the impact of the Covid19 pandemic