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The review analyses Inconel 718 (IN718) alloy, which is the nickel-based superalloy and has great application in industries due to its superior mechanical properties even at elevated temperatures by means of the solid-solution strengthening and precipitation strengthening. However, because of the tool over-wear, poor part surface integrity, high hardness and low thermal-conductivity properties, it is difficult to manufacture finished products with using conventional machining methods. It is especially urgent for the products of complex designs. In this regard, justification is given for the widespread use of modern additive manufacturing (AM) for the fabrication of the products from IN718. The most popular is AM based on the selective laser melting (SLM) technique, which can fabricate complex geometries with superior material properties. At the same time, the metal parts fabricated by SLM suffer from excessive residual porosity, residual tensile stress in the near-surface layer, and the formation of a relatively rough surface. In addition, the SLM-inherited surface defects can cause stress concentration to initiate cracks, reducing the fatigue strength of the printed parts. The review focuses on identifying potential solutions to the surface-finish complex additive manufactured to improve the surface properties to meet the industry requirements. Therefore, the improvement of the IN718-alloy-parts’ surface properties printed by the SLM becomes especially relevant. Currently, different surface post-processing technologies are being developed to obtain the expected surface quality of the SLM-components. As demonstrated, the finish surface enhancement treatments led to significant improvement in the wear resistance, corrosion resistance, increase in fatigue life, and tensile strength of the metallic materials. Therefore, adapting surface post-processing technologies has become a growing area of interest as an effective tool for improving the functionality and service lifetime of SLM IN718-alloy components. The review aims to analyse the main results of the most systematic studies of the currently developed surface post-treatments aimed to improving the surface-structure quality and properties of the IN718 parts fabricated by SLM. These results contribute to a better understanding of the role of the various-parameters’ effects on the surface improvements during the surface post-processing and changes in the structure–phase state, and physical, chemical and mechanical properties. Examples of the effects of a series of surface post-processing methods are presented: laser polishing, mechanical magnetic polishing, cutting finish-machining operations, shot peening, sandblasting technique, ultrasonic-impact treatment, and electrochemical polishing.

The goal of the review is to analyse the main published results of the most systematic studies of changes in the structural–phase state, the physical and chemical properties of the metallic single- and multilayer thin films’ systems after bombardment by the low-energy (

Currently, the interest in the application of metal additive manufacturing (AM), also known as 3D printing, is grown massively in the various fields of the industry and surgery. AM has significant multiple advantages compared to traditional subtractive technologies for making highly customized parts with complex geometries without causing noteworthy extra costs. Now, several powder-based AM technologies for metals’ 3D printing are in progress, in particular, selective laser sintering (SLS), selective laser melting (SLM), and electron-beam melting (EBM). In the past few decades, increasing research and developments are devoted to the wire-feeding-based 3D printing production of parts made of the Ti–6Al–4V alloy, which is widely investigated in different fields such as aerospace, automotive, energy, and marine industries as well as the prosthetics and the production of orthopaedic implants. Due to the feasibility of economical producing large-scale metal components with relatively high deposition rate, low machinery cost, high material efficiency, and shortened lead-time compared to powder-based AM, wire-feeding-based AM (WFAM) is attracting significant attention in the industry and academia owing to its ability for the production of the large components of the medium geometric complexity. In recent years, three options of WFAM are intensively researched, which differ by the wire-melting heating sources: wire + arc additive manufacturing (WAAM); wire-laser AM (WLAM), and wire electron-beam additive manufacturing (WEBAM). The purpose of the present review is systematic analysis of the mechanical properties of the Ti–6Al–4V alloy samples 3D-printed by WFAM with various heating melting sources, namely, arc, laser, and electron beam. Particularly, considering the literature data for the period of 2013–2020, such important properties as yield strength, tensile strength, elongation, and hardness are analysed for the samples in the as-printed and post-processed conditions.

During the last years, the interest in the application of the additive manufacturing (AM), also known as 3D printing, becomes extremely popular in the various fields of the medicine including the dentistry. Currently, metal and ceramic materials are most often used for dental prosthetics manufactured by 3D printing. The yttria-stabilized zirconia (YSZ) ceramics has become the best alternative for metal-based dental restorations. In this regard, the main goal of this review deals with studying the effect of the 3D printing parameters on the macro- and microstructure and, accordingly, on the mechanical properties of the sintered YSZ, and on this basis, to give the practical recommendations to clinical dentistry and further prospects. As most researched in recent years, the 3D printing methods of such ceramics are the Laser-Stereolithography (Laser-SL) and the Stereolithography-Digital Light Processing (SL-DLP) based on the vat-photopolymerization technology and are discussed here. The physical foundations and the technological parameters of these AM technologies are considered. The main attention focuses on the effects of the thermal conditions during the 3D printing on the solidification microstructure (density, grain size, and crystalline phase composition), which is controlled by the manufacturing technologies. In addition, the true hardness and the biaxial flexural strength of the 3D printed YSZ samples are discussed. At last, the advantages of 3D printing ceramics in dentistry are mentioned.

The review analyses the microstructure of the commercial Co–Cr–(Mo, W) dental alloys fabricated by 3D digital selective laser melting (SLM), which is the most promising technique among the emerging additive fabrication technologies used for metal products manufacturing in dentistry. In this regard, the main goal is to compare the microstructures of the metal dental products produced by two currently used technologies, namely, conventional casting and SLM. We consider the latest research published from 2013 to 2022. The microstructures are evaluated using optical microscopy (OM), scanning electron microscopy with energy-dispersive x-ray spectroscopy (SEM–EDS), x-ray diffractometry (XRD), electron backscatter diffraction (EBSD) pattern analysis, and atomic force microscopy (AFM). The microstructure analysis allows concluding whether the SLM fabrication process is suitable for dental applications. As shown, the microstructure of the Co–Cr dental alloys depends on both the chemical composition of the samples and the parameters of the manufacturing technique used. Experimental results have proven that, in contrast to the conventional casting, the SLM-fabricated specimens display superior microstructure due to complete local melting and rapid solidification. Additionally, the SLM process minimizes residual flaws and porosity. As a result, SLM allows producing the dense material comprising homogeneous fine-grain microstructure.

The literature data on the problem of modification of the structure and properties of the Fe-based rapid-quenched alloys by various methods of severe plastic deformation (SPD) are reviewed. The SPD methods such as Bridgman cell torsion, ball-mill processing and high-frequency shock treatment as well as their advantages and disadvantages are considered. By examples of a large number of amorphous Fe-based alloys, the influence on their structure and properties of each of the considered SPD methods is analysed. Based on the obtained data, the mechanism of deformation nanocrystallization of amorphous alloys is proposed.

In the state-of-the-art dentistry, the metal materials are widely used, and their number is constantly increases. The disadvantages of such materials include their electrochemical and corrosive activities in the oral cavity. A number of factors, such as chemical composition, microstructure, fabrication method, and surface treatment, can cause the electrochemical degradation of dental alloys. This review deals with alloys used in contemporary dental orthopaedics, concerns the effect of alloying impurities and protective coatings as well as modifying the structure and chemical state of the surface on its corrosion properties. Properly chosen alloying of metals allows not only increasing some of the corrosion-mechanical characteristics, but also, as a result, to prevent the occurrence of pathological manifestations in the oral cavity. Different types of high-energy surface treatments lead to specific changes in the physicochemical structure of the thinnest surface layer. A special attention concerns the methods of severe plastic deformation and laser treatment of the dental alloy surfaces. As shown, the improvement of the corrosion properties of dental metal alloys as a result of ultrasonic impact treatment occurs due to the nanostructuring of the surface and the formation of a surface layer with high-passivating properties. Laser irradiation also increases the corrosion resistance of dental alloys in the corrosive medium and results to a significant decrease in the value of the corrosion potential, thereby minimizing the negative effect of the metals of the alloy on the human organism. However, we have to note that the works aimed to improve the physicochemical properties of the dental-alloys’ surface via both the laser treatment and the ultrasonic impact processing are currently at the initial stage of their development and has not yet received practical application in the dentistry.

The paper is concerned with the description of the physical nature of the dependence of the sputtered-atoms’ ionization probability on the atomic and electronic structures of a metal target bombarded with ions of neutral gases (matrix effect). A systematic analysis of the literature data and results of authors of this review is carried studying the secondary ion emission (SIE) of pure metals, dilute solid solutions, and concentrated alloys. The practical importance of such studies is because the phenomenon of renewable energy is the basis of a unique method of chemical, isotope as well as physical and chemical analysis not only of metallic materials, but of semiconductors and organic substances too. The high sensitivity of SIE to the change in the forces of interatomic interaction and the parameters of the electronic structure is revealed. Experimental and theoretical studies in this direction have made it possible to deepen the knowledge of the nature of the phenomenon of secondary ion emission that arises when metal targets are bombarded with inert-gas ions, and to outline ways for further studying and applying this phenomenon for diagnostics of solid surfaces and bulks. Particularly, the method of mass-spectrometry of secondary ions based on the SIE can be used to study the phase equilibrium diagrams as well as the first and second kind phase transformations. Taking into account the high sensitivity of SIE to the change in the forces of interatomic interaction and the parameters of the electronic structure, further investigations should be aimed at establishing stricter correlations between these properties of the material and such characteristics of SIE as the emission coefficient and the ionization probability of sputtered atoms. The solution of this problem will create a new quantitative method for determination of the binding energy of various atoms in the composition of multicomponent materials.

Мета. Покращення результатів лікування хворих з місцево-розповсюдженими та рецидивними солідними пухлинами черевної порожнини та заочеревинного простору. Матеріали і методи. За період з червня 2015 по січень 2018 р. в Національному інституті раку виконали комбіновані оперативні втручання з нефректомією 28 хворим з приводу первинних місцево-розповсюджених та рецидивних солідних пухлин черевної порожнини та заочеревинного простору. Результати. У 5 із 28 пацієнтів виконали нефректомію ex vivo ex situ з аутотрансплантацією нирки, у 4 - успішно. Гостре ушкодження нирок спостерігали у 6 (26%) хворих, яким аутотрансплантації нирки не виконували. Після операції померли 2 (8,7%) хворих. У пацієнтів, яким нирка була збережена, не спостерігали гострого ушкодження нирок, ніхто з цих пацієнтів не помер. Висновки. З метою профілактики розвитку гострого ушкодження та хронічної хвороби нирок у майбутньому можливість виконання аутотрансплантації нирки у разі хірургічного лікування солідних пухлин черевної порожнини та заочеревинного простору, окрім первинного раку нирки, повинна бути розглянута щодо кожного хворого. Дану процедуру доцільно виконувати в спеціалізованих лікувальних закладах, де накопичено досвід в онковаскулярній хірургії.

It is well known that the metal-surface properties vary as a result of the surface layers ion sputtering in vacuum. This review contains results of the studies of kinetics change of oxygen adsorption and oxidation on the surface of transition metals and alloys in a vacuum during the low-energy (< 10 keV) Ar+ ions bombardment. Particularly, the results of the systematic studies of the surface of Cu, Ni, Fe, Co single crystals, and Fe–Ni alloy are presented. The important role of such parameters as a dose of the ion bombarding, ion energy and sample temperature in the chemical activity of surface is noted. It is argued that mechanism of interaction in surface–gas system is substantially controlled by the optimal ratio between the energy and primary ion current density, as well as sputtering rate of natural oxide on the target surface.

This review work is dedicated to the 70th anniversary of the G.V. Kurdyumov Institute for Metal Physics of National Academy of Sciences of Ukraine (1945–2015). The review reports on the results of investigations of dynamic characteristics of the surface of ferromagnetic single-crystal Fe–Ni and Co–Ni alloys obtained in department of the surface atomic structure and dynamics. Interest in the study of the surface dynamic properties of the metals and alloys is caused by the fact that the explanation of many physical, chemical, and mechanical properties of the surface materials and their macroscopic behaviour is directly or indirectly associated with the consideration of the vibrational motion of the surface atoms. The developed new method for complex non-destructive layer-by-layer analysis with monolayer resolution allows studying the atomic structure, element composition, and dynamic characteristics (Debye temperature, mean-square displacements of atoms, the coefficient of thermal expansion and the force constants). The change of the interatomic forces occurring during the phase transformations in surface region of the ferromagnetic alloys it determined. Magnetic ordering causes significant changes of both harmonic and anharmonic components of interatomic interaction forces. In turn, this leads to changes of thermal expansion coefficient within the range of ferromagnetic Curie temperature and also to the appearance of a contribution to the dynamic characteristics. It is obvious that these changes in the surface differ from the crystal bulk due to the specific distribution of the interatomic interaction forces in the surface layers.

The historical essay on development of fuel cells in Ukraine is given. Taking into account advantages of Ukraine on a deposit of zirconium, work on ceramic fuel cells are actual. The detailed technology of reception of electrolyte and ànode and their researches at a modern level is resultated. A series of fuel cells and their batteries are made tested.

Economic essence of the category "investments", genesis of investment theories was considered in the article, the comparative analysis of existing definitions is carried out and is analysed characteristic features of investments. Value of investments at macrolevel, mesolevel and microlevel of their realization was defined.

Impact of duration of holding of various-composition amorphous ribbons within the 0.17 T magnetic field (MF) on their microhardness is investigated for the first time. Ribbons are held in the air at room temperature. Non-monotonic dependence of microhardness on holding duration in MF for samples of amorphous metal alloys (AMA) is revealed. Such a feature manifests itself for both magnetic and non-magnetic AMA. Long-term holding in MF results in strengthening of AMA. As suggested, the detected magneto-mechanical effect is caused by transition of the amorphous alloy under MF action into a new structural state with different short-range order parameters and level of internal stresses.

A method of the electron energy loss spectroscopy is used to investigate a manifestation of the plasmons in the secondary electron emission spectra for the ordering Pt80Co20(111)Pt80Co20(111) alloy. The method is offered for determination of a ‘surface–bulk’ boundary based on the dependences of line intensities of the surface and bulk plasmons on the primary-electron energies within the range of 150–700 eV. As revealed, the thickness of nanosize surface layer for the disordered Pt80Co20(111) alloy is twice as much than thickness for the ordered state. Under ordering of an alloy at issue, the greater quantity of conduction electrons takes part in plasma oscillations.

Теоретически исследуется осаждение алмазоподобного покрытия в импульсном режиме, в котором осаждаемый поток ионов плазменной среды с энергией E0 ~ (20÷200) эВ модифицируется путем наложения импульсного потенциала U ≤ 1000 В. Показано, что внутренние напряжения в алмазоподобном покрытии (АПП) при импульсном режиме осаждения могут быть уменьшены в несколько раз без существенного уменьшения концентрации sp3-связанного углерода, по сравнению с АПП, полученным в стационарном режиме осаждения при энергии ионов E0. Предложен метод оптимизации параметров импульсного режима, основанный на анализе положения траекторий термоупругих пиков ионов на фазовой P,T-диаграмме углерода.

Висвітлено процес адаптації спеціаліста до первинної посади державної служби системи соціального захисту населення та проблеми службової взаємодії з новим соціальним працівником керівників, спеціалістів кадрової служби.

The review is devoted to the state-of-the-art views on the microstructure evolution in structural and tool carbon steels during the surface severe plastic deformation (SPD). The main focus is on the effects of the nanocrystallization in the near-surface area of the low-carbon steel (C 0.05–0.2%), medium-carbon steel (C 0.35–0.65%), and high-carbon steel (C 1.0–1.5%). It is reviewed the following advanced surface SPD methods for the metal surfaces in recent years: an ultrasonic impact peening (UIP), high-frequency impact peening (HFIP), air blast shot peening (ABSP), surface mechanical attrition treatment (SMAT), and laser shock peening (LSP). Microstructure evolution before and after SPD is studied by optical microscopy (OM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The effects of the SPD parameters on the nanocrystalline modification of such main phase components of the carbon steels as ferrite, pearlite and cementite are analysed. The atomic mechanism of the nanocrystallization is presented. The strain-hardening effect induced by SPD is demonstrated by the data of the near-surface microhardness profiles.

Secondary ion mass spectrometry (SIMS) is successfully used for fundamental and applied studies of the solid surfaces. Thus, it is important to know regularities in the secondary ion emission (SIE) induced by the primary beams of the inert or chemically active elements. The SIE intensity is found to be dependent not only on the surface sputtering processes (the intensity increases with the atomic number of the bombarding ion), but on the ionization probability of the sputtered atoms (the probability is strongly dependent on the physical and chemical states of target surface and experimental conditions) too. Analytical capabilities of SIMS might be improved by the use of light ions producing low sputtering and causing minimum surface erosion. The goal of the present review paper is a systematic study of various SIE aspects for metals, alloys, and chemical compounds in the case when the surface is bombarded with lightest ions — protons. To reveal the possibilities of proton applications in SIMS, the target surface was also bombarded with argon ions. The SIE regularities for metal targets were studied on the ion microprobe analyser equipped with a spherical 180°C sector energy analyser and a system, which pumps gas into the chamber. This made it possible to investigate not only the SIE factors, but also the secondary ion energy distribution and the change of the emission character at the target interaction with active gases. The SIE coefficients are measured for metals of I–III large periods. The use of primary protons and argon ions leads to a similar dependence of the SIE differential coefficients on the target atomic number. The SIE coefficients for primary protons and argon ions for the same elements are similar. Sputtering coefficients for the Ar+ ions are known to exceed those for protons. The fact that the metal-ion emission intensity for bombardment with lighter ions commensurate with a signal of secondary ions sputtered from the surface by heavy species is of a high practical importance for use of protons with analytical purposes. This fact may be explained as a result of extraordinary high ionization probability due to H+ ions. However, along with the general regularities based on the nature of materials at hand, there are essential differences in mechanisms of the atom ionization for the sputtering by protons and inert gas ions. Therefore, we have investigated the energy distributions of metal secondary ions ejected from surface bombarded with H+ and Ar+ ions. It is shown that, in the case of proton bombardment of multicomponent targets, a partial suppression of the structural, phase, and other matrix effects is observed. These effects as well as the increasing ionization probability of metal atoms sputtered by protons are quantitatively described concerning the important role of the local surface bonds in the ionization mechanism.

The article considers issues of the individual goal orientation and offers a methodology of its research. The development of the space-time continuum of situations made it possible to identify four types of the future, present and past situations. The past time is divided into 2 types: actual (acquired) and deep (generic memory). Particular emphasis is placed on the features of the remoteness of goals, which is divided into 3 types: close, medium and long-range goals. The close goals are related to the situations of the past, which characterize the biological level of the individual and the egocentric position. The medium goals are related to the rational position, and the long-range goals to the altruistic position. Self-development processes are also established as self-determination, self-realization, self-improvement and self-actualization. The article focuses on future situations where emphasis is placed on long-range goals corresponding to the altruistic position of the individual.

The article studies and analyses classification features of investments, provided by domestic and foreign economists. It systemises main classification features and identifies such ones that facilitate identification of investments as an economic category. It considers the most frequently used, from the point of view of revelation of economic essence of the “investments” category, classification features: by the object of investment, by the term of investment, by regional features of investment, by forms of ownership on investment resources, by the degree of risk and by the character of participation in investment. It presents a classification of investments with consideration of execution of the investment process, which would allow systematisation of understanding the essence of classification features of investments in accordance with the investment process.В статье исследованы и проанализированы классификационные признаки инвестиций, представленные отечественными и зарубежными учеными-экономистами. Систематизированы основные классификационные признаки, определены такие, которые способствуют идентификации инвестиций как экономической категории. С точки зрения раскрытия экономического содержания категории "инвестиции" рассмотрены наиболее часто используемые классификационные признаки: по объекту вложения инвестиций, по сроку инвестирования, по региональным признакам инвестирования, по формам собственности на инвестиционные ресурсы, по степени риска, по характеру участия в инвестировании. Представлена классификация инвестиций с учетом осуществления инвестиционного процесса, который позволит систематизировать понимание сущности классификационных признаков инвестиций в соответствии с инвестиционным процессом.

The article gives a review to the questions of the goal orientation of the personality, examines the problems of the goals’ functions from the position of the orientation. The author identifies the factors of personality which provide functioning of the goals, describes the structure of personality through the prism of the goal orientation. There is also a suggested periodization of macro and micro cycles of the human’s life journey.