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Item type:Наукова стаття, Investigation of Cylindrical Particles Sphericity and Roundness Based on the Extreme Vertices Model(Springer Nature Switzerland, 2024) ; Заболотний, Олег Васильович; Гульчук, Юрій Миколайович;In this scientific investigation, the article's authors have created a three-dimensional computer simulation model to explore the sphericity and roundness of elements, specifically particles. The authors elucidated the detailed calculation of the sphericity of elements and roundness of elements for cylindrical particles through the application of the extreme-vertex 3D model. Based on the proposed extreme vertex model theory, the points at which linear constraints intersect were optimized, allowing for the maximum approximation of the form factor to unity. Furthermore, the proposed theory of extreme vertices in the context of modeling elements, particularly in voxel-based modeling, is of significant importance in defining the boundaries and limits of objects in three-dimensional space. Moreover, it was discovered that this idea holds importance in the context of the simplex-complex method, a commonly employed algorithm for addressing linear programming problems. Additionally, correlations between the sphericity and roundness of elements and the particle diameter were examined, enabling the prediction of particle shape. This is because the obtained sphericity values mostly approximate 1, which implies that the elements have a spherical or nearly spherical shape.Item type:Наукова стаття, Optimization of 3D Computer Model Parameters for Spherical Elements Modeling(Springer Nature Switzerland, 2024) ; Заболотний, Олег Васильович; Гульчук, Юрій Миколайович;The scientific chapter discusses the simulation of spherical elements using a developed computer model. We documented the primary combinations of spherical particles that occur during filling in the hopper. The modeling revealed that the most common combination for spherical elements consists of three balls, forming an equilateral triangle in the cross section passing through the centers of the balls. In the case of a structure with four spherical balls, connecting their centers creates a rhombus in the cross section. Notably, this combination generates two smaller equilateral triangles within the rhombus, influencing the process of pushing the spherical balls apart. This process, in turn, facilitated the observation of contact between spherical elements and established the stable position of each individual particle.Item type:Наукова стаття, Improvement of Processes for Obtaining Titanium Alloys for Manufacturing Parts with Design Elements(Springer International Publishing, 2021-11-18) ; Заболотний, Олег Васильович; Ilchuk, Nataliia; ; Гульчук, Юрій МиколайовичThe article presents a systematic block diagram for manufacturing TiAl titanium alloys. Based on the developed block diagram of TiAl components, the main already known stages of powder metallurgy manufacturing technology were improved. Based on the obtained chemical reaction of structurally inhomogeneous materials, the intermetallic phase relationship of titanium aluminides was revealed. It is studied that in the zone of interaction of the composition of titanium and aluminium components, a certain thickness of the transition layer is formed, which practically does not change with increasing exposure time. The crystallization process of inhomogeneous TiAl materials was studied in more detail using the constructed crystal lattice of titanium alloys. As a result, the formation of an atomic grid in space was observed. It should also be noted that the recognition of individual areas in microstructural images was carried out using the Smart-eye software package. The microscopic analysis allowed us to predict the main structural characteristics of TiAl components. In particular, to carry out more detailed control of the particles of TiAl components, their density, porosity, relationships with each other, the shape and size of TI and Al powders. The structure of the interaction of TiAl materials and the interpolation dependence of the formed intermetallic layer are also presented. Based on the conducted research, the quality indicators of parts with structural elements, particularly gears, have been improved.Item type:Наукова стаття, Study of the Porosity Based on Structurally Inhomogeneous Materials Al-Ti(Springer International Publishing, 2021) Заболотний, Олег Васильович; Ilchuk, Nataliia; Гульчук, Юрій МиколайовичA technology for forming structurally inhomogeneous materials of Al-Ti samples has been developed. The components of the initial mixture were calculated based on the bulk of real powders, taking into account the mass, stoichiometric coefficients of the original components, the purity, and the bulk density. The microstructure of structurally inhomogeneous materials samples was studied using application programs. Besides, image recognition is performed at various magnifications before etching and after etching. The main properties of Al-Ti materials at different temperatures are obtained. An interpolation of the porosity dependence is constructed based on theoretical and experimental data. It is proved that the granulometric composition of structurally inhomogeneous materials has been improved based on the correct percentage of the initial mixture. The dependences of porosity on pressure and melting temperature for manufacturing structural parts are substantiated and constructed. Thus, there is reason to argue that improving the granulometric composition of Al-Ti based on a correctly selected percentage of the initial mixture, taking into account the further process of forming structurally inhomogeneous materials, allows to control such a parameter as porosity, as well as to study the physical and mechanical properties in the manufacture of various structural purposes parts to predict their structures.