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The features of formation of the structure, composition and certain mechanical properties of layered materials based on titanium and its alloys during melting by the electron-beam cold-hearth melting technique are considered. The influence of composition in two-layer structures Ti64 (Ti–6Al–4V)/LCB (low-cost beta Ti–1.5Al–6.8Mo–4.5Fe) and Ti64/Ti5553 (Ti–5Al–5V–5Mo–3Cr), as well as 4-layer Ti5553/Ti64/c.p.Ti (commercial purity titanium)/Ti64 is studied. The processes of formation of transition layers at the boundaries between alloys after both the smelting and the subsequent deformation by rolling, as well as after heat treatments, are studied. A relationship is established between the composition and the formed microstructure, on the one hand, and hardness, strength, ductility, and fracture under 3-point bending, on the other hand. A comparison of the titanium-layered materials produced by this method with the results provided by other technological approaches is carried out, and the advantages of the proposed technology are shown.

The presence of impurities of other metals in titanium alloys affects the composition of the oxide film after heat treatment: in addition to rutile, the VT 00 alloy contains Ti6O oxide, which in the VT 1-0 and VT 6 alloys is transformed into Ti3O oxide, which affects the corrosion resistance and mechanical strength. Calcium phosphate coatings containing brushite, calcite and apatite were obtained by electrochemical deposition on titanium plates at room temperature, pH 5, and a constant current density of 30 mA/cm2 from a suspension electrolyte CaCO3 / Ca(H2PO4)2. A layer of amorphized apatite was applied to the coatings using the biomimetic method in a 3-fold concentrated model solution of Simulated Body Fluid to improve biocompatibility. After heat treatment at 800°C, calcium phosphate coatings obtained on titanium VT 00 have greater biocompatibility, but lower resorbability, due to the presence of a larger amount of crystalline hydroxyapatite in the coating.

Bilayer samples comprised of hard metal-matrix composite top layer and ductile 10 mm Ti–6Al–4V plate are produced with 3D printing by conical electron-beam method using specially prepared core (powder) wire that allows forming hard top layer of metal-matrix (Ti–6Al–4V) composite (MMC) reinforced by means of fine TiC particles with thickness up to 4 mm. Ballistic tests performed with 7.62×51 AP ammunition show a good ballistic resistance of this protective structure, i.e., it is not perforated. Only minor penetration and partial fracture are occurred exclusively in the surface MMC layer. Either no traces of plastic deformation are found at the boundary with the base layer or inside it that indicates that the MMC layer absorbs the entire impact energy of the projectile. Based on studies of the fine structure and texture of the interface between the layers, a reasonable assumption is made that wavy geometry of MMC layer provides additional deflection and scattering of stress waves generated during impact. Comparing the results of ballistic tests of various metallic materials, it is concluded that the 3D-printed bilayer material consisting of the upper Ti–6Al–4V + 40% TiC layer and the base Ti–6Al–4V layer has an undeniable advantage in ballistic performance when it is tested with cartridges of this type.

In this paper, a new approach for additive manufacturing metal-matrix composites based on Ti–6Al–4V titanium alloy reinforced with titanium carbide particles, as well as layered structures consisted of such composite and Ti–6Al–4V alloy layers is considered. The approach is based on 3D printing with a conical electron beam using a special cored wire, whose composition corresponds to metal-matrix composite. The issues of production such a wire, the features of the 3D printing process, when using it, as well as the features of formation of the microstructure and phase composition of the printed composite material are described. The issues of titanium-carbide particles’ wetting with Ti–6Al–4V melt during process of 3D printing, as well as possible thermogravitational effects (floating or drowning) for solid TiC particles within the melt are considered in detail with additional experiments. The influence of individual components of the wire composition on the formation of the microstructure and its uniformity over the cross section of the printed layer is shown. The possibility of controlling the formation of homogeneous structural state and obtaining sufficiently high values of the hardness (of above 600 HV) of the metal-matrix composite layer printed on the Ti–6Al–4V baseplate is shown.

The growing relevance of 3D printing of finished metal products in recent years is due to the reduction of costs for manufacturing, machining, changing the standard sizes and nomenclature of parts, the possibility of obtaining solid parts with complex internal geometry. One of the most promising 3D printing processes, which provides a wide range of productivity (0.02 - 25 kg/h and more) with the possibility of surfacing a wall with a thickness of 2-20 mm, is additive plasma-arc surfacing (APDN) with wires and powder materials. The work examines the current state of research on additive manufacturing of metal parts from steels and alloys, determines the state and prospects for the development of APDN. It is shown that APDN allows performing 3D printing using a wide range of implant materials, in particular, compact and composite (powder) wires, powders of light alloys and refractory metals, composite powders and mechanical mixtures of powders of alloys, metal ceramics, carbides, borides, etc. New opportunities for the application of APDN include development of technologies for growing products from materials with gradient functional properties, from dissimilar materials, with accompanying modification of the deposited metal by additional processing, improving the properties of the deposited metal due to the use of hybrid processes. The state of innovative developments of APDN technologies and equipment carried out at the E.O. Paton Electric Welding Institute of the National Academy of Sciences of Ukraine, and their industrial implementation is highlighted. 32 Ref., 5 Tabl., 22 Fig. [ABSTRACT FROM AUTHOR]

Relevance. Titanium and its alloys are the most durable and corrosion-resistant metal materials that makes them widely used in mechanical engineering, aircraft and machinery, chemical apparatus construction, medicine. The use of such construction materials with increased resistance in aggressive environments makes it possible to increase the efficiency of technologies for processing natural raw materials (high-pressure reactors, centrifuges, separators, high-speed pumps, heat exchangers, communications), the production of chlorine and alkalis (evaporators, electrolysis equipment), organic synthesis (equipment for the production of halogen derivatives), the production of nitric acid, ammonia and nitrogen fertilizers. The combination of mechanical and thermal treatment of alloys, including the use of severe plastic deformation, allows modifying their structure and obtaining materials with improved physical and mechanical characteristics. Purpose: to determine the effect of various modes of the deformation and heat treatment of titanium alloys VT6 and VT22 on their corrosion resistance in aqueous solutions of acids, alkalis and salts. Objects: samples of VT6 and VT22 alloys with different structures, aqueous solutions of acids, alkalis and salts. Methods: DC voltammetry, gravimetry under conditions of free corrosion, optical microscopy, scanning electron microscopy, X-ray diffractometry, atomic emission spectroscopy. Results. Under conditions of severe plastic deformation, samples of titanium alloys VT6 (triaxial pressing in the temperature range from 550 to 800 °C) and VT22 (radial shear rolling in the temperature range from 750 to 850 °C, additional cold rolling of hot-rolled samples, aging at 550 °C for 3...6 hours) with ultrafine-grained structure have been produced. It was found that VT6 alloy with ultrafine-grained structure has less corrosion resistance under conditions of free corrosion in solutions of sulfuric acid of a high concentration (5 M), as well as in 3,5 % NaCl solution at anodic polarization compared to the initial alloy with coarse-grained structure. The main types of corrosion damage to the surface of the ultrafine-grained samples were ulcers and pitting, whereas for samples with a coarse-grained structure, continuous corrosion was characteristic. The increase in the rate of corrosion and morphological features of the destruction of the surface are explained by structural-phase heterogeneity and segregation of alloying elements as a result of the deformation and thermal effects. The corrosion resistance of VT22 samples with an ultrafine-grained structure correlates with the content of the b-phase and with the features of the interphase distribution of alloying elements resulting from the polymorphic transformation of a-TiDb-Ti under conditions of the deformation and heat treatment. It is shown that VT22 samples after hot rolling are the most stable in acid solutions (0,1 M HCl, H2SO4) and the least stable in alkali solution (0,1 M NaOH) compared to samples treated under other regimes. In a 3,5 % NaCl solution, the ultrafine-grained sample VT22 showed the least resistance after additional cold rolling due to a large concentration of structural defects that contribute to increased corrosion cracking of the material. The interpretation of the experimental results was carried out using theoretical calculations of the equilibrium composition of corrosion products formed in the multicomponent systems under study.

Natural metal composite materials represent a promising class of modern structural materials that need to be welded. Such materials can be welded by fusion, as has been established with the Ti-TiB alloy as an example. The enhanced operational properties of such materials are determined by the microstructure, which is characterized by the presence of microfibers of borides, carbides, or silicides in the metal matrix. To preserve the mechanical properties of materials in a welded joint, it is necessary to ensure the formation of reinforcing microfibers in the welded seam material. Determination of formation mechanism of boride microfibers, originated in the welded seam material, will become the basis for optimizing of fusion welding modes, in particular, electron beam welding mode. The purpose of this study is the determination of formation mechanism of boride microfibers originated in the welded seam material. Two most probable variants of the formation mechanism are analyzed, which involve eutectic decomposition during crystallization from a liquid melt or eutectoid decomposition from a metastable crystallized alloy. The third version is a mixed variant of the two above-mentioned mechanisms. In the article the results of metallographic analysis of features of boride phase distribution and an analysis of elemental composition of boride fibers based on local Auger electron spectroscopy are presented. The object of study was a Ti-TiB alloy joint obtained by electron-beam welding. The analysis factors were the features of size, orientation, and nature of the distribution of boride phase microfibers in different areas of the welded seam. The characteristic elemental composition of boride microfibers, which characterizes the correspondence to equilibrium phases, is also studied. The degree of deviation of the ratio of boron and titanium in such a phase from the thermodynamically equilibrium in different layers of the material of the welded seam, formed by an electron beam in vacuum, is determined. The dependence of boride phase distribution under various conditions of heat exchange in the welded seam material on the side surfaces and in the central regions is established. It is shown that some of boride microfibers formed in the material of the welded seam are characterized by a deviation from the thermodynamically stable composition ТіВn (n = 1) to ТіВn (n = 0.85). The dendritic nature of boride microfibers distribution and the presence of meta-stable phase formations on Ti and B basis provide the grounds for proposing the predominant mechanism for the formation of structure of the welded seam material in the Ti-TiB alloy during crystallization. An analysis of hypothetical variants of the formation mechanism of boride microfibers originated in the welded seam material showed that the formation of a dendritic type of structure is characteristic for the growth of crystals of a new phase in the liquid phase. Such growth is characterized by the formation of equilibrium phases. The presence of a significant amount of non-equilibrium boride phase in the welded seam indicates the residue of non-equilibrium boron in the titanium matrix and continuation of growing of boride fibers in the crystallized welded seam. A determined mechanism for formation of boride microfibers originated in the welded seam material is eutectic decomposition during crystallization from a liquid melt with the formation of TiB microfibers and further growth of such crystals due to eutectoid decomposition from a metastable crystallized Ti-TiB alloy. The results obtained make it possible to understand the mechanism of formation of a welded seam in welded natural-composite metal materials, which permits to develop the recommendations for optimizing the welding technology for such materials.

Potential of additive manufacturing technologies, namely, xBeam 3D Metal Printing for the fabrication of uniform Ti–6Al–4V (Ti-6-4, mas.%) material as well as layered titanium-based structures, with mechanical properties sufficient for wide practical application is demonstrated. The key distinctive features of this process are titanium alloy wire as a feedstock material and hollow conical electron beam for heating and melting of the wire. 3D printed with special ‘shift strategy’ Ti-6-4 alloy meets requirements to mechanical characteristics of corresponding conventional cast and wrought products, if microstructure features, material anisotropy and crystallographic texture are controlled with proper selection of processing parameters. Production of multilayered materials consisting of combined layers of different titanium materials, viz. commercially pure titanium (CP-Ti), Ti-6-4 and high-strength T110 alloys, as well as metal matrix composites (MMC) based on Ti-6-4 matrix reinforced by fine TiC particles is considered. Microstructural features and mechanical properties of all 3D printed materials are investigated. Terminal ballistic tests are performed with different ammunition. Described results show the promising potential of 3D printing technologies, xBeam 3D Metal Printing as an example, for manufacturing of titanium-based multilayered armour materials with reduced thickness and weight, and at the same time, sufficient protection characteristics.

The influence of the beam current, the distance between the beads of the clad material and the wire feeding intensity during electron‑beam (EB) surfacing of titanium alloy VT9 on the thickness and uniformity of the resulting restoring coating was investigated. As the beam current strength increases, the width of the deposited layer increases and the height decreases. The optimal distance between the beads should be considered an offset that does not exceed the width of the bead. It is possible to control the height of the deposited layer in a wide range by precise dosing of the wire feed intensity. The uniformity of surfacing is ensured by a balanced energy impact. Chemical composition of the clad layer meets the requirements of normative documents on the content of impurity gases for products from medical materials, obtained by additive technologies. The results of the study are used in the restoration of the surface of the landing gear element of aviation equipment.

Linear friction welding is an advanced technology for manufacturing titanium blisks for gas-turbine engine compressors, which are subjected to stringent requirements for cyclic strength and dimensional accuracy. Substitution of conventional butt joints with more technological T-shape joints is a promising area, which provides reducing of the pre-welding machining costs. The introduction of T-form joints requires additional research of thermal distribution specifics and strain-stress state formation in the welding process and after its end. Therefore, the study of residual stresses in titanium alloy T-shape joints produced by linear friction welding is topical. The paper investigates the residual stresses in imitating welded blisk joints. The authors consider the results of welding where the blade imitator has a reamed relief of a smaller section. The finite element model covering forging, cooling, and disassembly of welded specimens is offered. The authors developed the model in ANSYS Workbench to describe the strain-stress state of welded specimens, which allows for estimating the residual stress levels and spreading. The main distinctive feature of the model is an accounting of asymmetric temperature distribution obtained by finite-difference solving of a T-shape joint thermal problem and weld shape simulation obtained as a result of welded joints metallographic research. The presented model allows the evaluation of the residual stresses in joints. The distribution of residual stresses in T-shaped welded joints is specific – compressive stresses existing in a weld are balanced by tensile stresses acting at a distance of 1 mm from the joint. The formation of compressive stresses in a weld is caused by plastic deformation due to the forging force action.

Drilling holes in titanium alloy VT-3 is a difficult task due to its poor machinability. The evaluation of the helical milling process is carried out by comparing the axial force, surface roughness and diametrical accuracy of the hole with the conventional drilling process. Holes created with helical milling have a high surface quality at lower axial feed, while the drilling process is accompanied by a higher axial feed, which leads to vibration of the cutting tool. When manufacturing high-precision holes in the elements of fuel control equipment, it is recommended to use helical milling.

The necessity of systematic formation of intellectual connections for integration into a single complex of currently fragmented software products for the technological analysis of the castings geometry, thermodynamic modeling of the titanium alloys properties, calculation of molding mixtures thermophysical characteristics for the purpose of conjugate implementation of a set of modeling procedures and casting processes diagnostics of is proved. Lack of such an integrated software package, computer analysis of modeling results in the existing manufacturing products practice demonstrates (by the example of the shrinkage defects distribution in a responsible casting of TL3 alloy) the need for radical technological design tools’ improvement.One of the key components of the “digital technology” being formed in the future is thermodynamic modeling of equilibrium phase transformations, which allows calculating the physico-chemical parameters, thermodynamic, thermophysical and casting parameters of titanium alloys and their evolution in the temperature range of crystallization. Based on thermodynamic simulation, experimental planning apparatus and the experience of statistical analysis carried out, a method for forming models for estimating equilibrium parameters used in modeling foundry processes has been developed, and it shows the possibility of applying it to various casting titanium alloys. For the standard composition of the TL3 alloy, a multifactor system of equations was obtained, reflecting the degree of influence of the components on the fluctuations of the alloy characteristics complex, which determine the development of a series of casting defects. The possibilities of using the obtained models for TL3 alloy and methods of obtaining them for use in computer modeling systems to increase the adequacy and accuracy of the results obtained are described.

The relevance of the research is caused by the fact that one of the most important factors in the failure-free operation of oil and gas equipment is the corrosion resistance requirements. Titanium alloys properties like high corrosion resistance in corrosive environments and high strength combined with low density make it possible to obtain products with high strength and low weight when operating in corrosive environments. However, titanium alloys usage in the manufacture of details that operate in an aggressive environment, including for oil and gas equipment, is limited due to both low machinability and low thermal conductivity, as well as the technological system predisposition to intense fluctuations. Object: productivity and economic efficiency from using mills for manufacturing of hull details like «case» type from titanium alloy. The main aim of the research is a development of rational machining modes and tool geometry for milling hull elements from titanium alloys. That can ensure maximum tool life, machining quality, productivity and economic efficiency. Methods: production tests of mills with different geometry of cutting edges by the multifactor experiment method using a vibro-diagnostic complex for determine the minimum vibration level zones during machining of the «case» type part from titanium alloy. Results. The authors have developed the recommendations to reducing vibration during milling hull elements from titanium alloys. This method allows finding the rational cutting conditions according to both the highest productivity and maximum tool life criteria in production conditions during the stage of debugging the technological process.

At brazing dissimilar joints of AD1 aluminium to VT1-0 titanium at the temperature of 605…610 °С by Al–12Si brazing filler metal in argon application of reactive flux of KAlF4 –10K2 SiF6 system with additives of CoF2, K2 ZrF6 compounds, promotes production of a sound joint due to formation of a low-melting alloy of Al-Si system on the contact surface. The low-melting alloy of Al-Si system newly-formed at reactive-flux brazing can independently fulfill the function of brazing filler metal at formation of a dissimilar metal joint. Cobalt reduced from the flux has little influence on weld structure and joint strength. At application of Al–12Si brazing filler metal and reactive flux of KAlF4 –10K2 SiF6–5K2 ZrF6 system, which contains potassium-zirconium fluoride (K2 ZrF6 ), a certain refinement of the structure (dendrites of aluminium-based solid solution) is observed from the aluminium side that promotes an improvement of shear strength of aluminium-titanium brazed joints. 33 Ref., 3 Tabl., 8 Fig. [ABSTRACT FROM AUTHOR]

The paper presents the results of studies on production of layered composite materials, based on aluminium and titanium alloys, by vacuum diffusion welding, with a broad range of specific weight values, which is achieved due to different layer ratio in each of the composites. Based on a layered composite material, a procedure was proposed for manufacture of three-layer honeycomb panels by vacuum diffusion welding. It is found that the average compressive strength of the three-layer panel with a filler from a layered composite material based on Al–Ti alloys is equal to 47.3 MPa, that is four times higher that the strength of similar honeycomb elements made from an aluminium alloy. It is shown that the layered material has higher thermal stability, compared to aluminium alloys. Sample annealing at the temperature of 700 °С for 30 min does not lead to their early destruction or loss of shape. [ABSTRACT FROM AUTHOR]

Copyright of Problems of Friction & Wear is the property of National Aviation University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nanosistemi, Nanomateriali, Nanotehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Приведены результаты исследования распределения водорода в сварных соединениях, выполненных электронно-лучевой сваркой титановых сплавов ВТ20 и ВТ23. Распределение водорода в сечении сварных соединений измерялось в зоне сварного шва, термического влияния и в основном металле посредством спектрального анализа с применением низковольтного импульсного разряда на спектрографе ИСП-51. Установлено, что пики водорода в неразъёмных соединениях, выполненных электронно-лучевой сваркой, в отличие от аргонодуговой сварки находятся не только в зоне термического влияния, но и в центральной части сварного соединения. Химическим анализом изломов неразъёмных соединений, исследованных с применением сканирующего растрового электронного микроскопа Hitachi S-3400N, установлено, что поры в сварных соединениях, выполненных электронно-лучевой сваркой, возникают вследствие десорбции в расплав капиллярно-конденсированных загрязнений, находящихся в дефектах поверхности торцов кромок, и избирательного плавления по границам зёрен из-за недостаточных температурных условий плавления по цельному зерну. Выявлено, что на появление изменений содержания водорода, с образованием дефектов, оказывают влияние температурные условия разогрева свариваемых кромок, скорость сварки, толщина свариваемых заготовок.

Using the results of computer modeling and experiment, an analysis has been made of the effect of hydrogen and its kinetics on the nature of the formation of cluster-block configurations in alloys – Laves phases based on Friauf polyhedra and kagome structures that determine the characteristics of new materials with the aim of advancing the ecological and energy-saving technologies for producing ultrapure hydrogen and then its accumulation in the concerning alloys.

Under the conditions of the fast crystallization of melts, the effect of hydrogen on mechanisms of structural transformations in V85Ni15 and V(85-x)TixNi15 alloys was experimentally studied. Structuring of phase compositions, diffusion, and hydrogen permeability were simulated. The regularities of improving the structural characteristics of alloys as a result of alloying with titanium, as well as the effect of hydrogen dynamics on the stability of the formed phases are revealed.

Background. Despite the annual increase in the number of operations using titanium alloy products, the problem of developing periprosthetic infectious complications remains unresolved. The promising direction in traumatology and orthopedics is the creation of implants that prevent the formation of biofilm on the surface of the medical device. It was proposed to apply an antibacterial coating to the implant surface, including vancomycin as the active component and the polymer polylactideco- glycolide as the carrier. The aim of the research was to study the antibacterial effect of the coating titanium blocks in vitro and analyze the dynamics of changes in the level of basic hematological and biochemical parameters at different periods after implantation in rats. Materials and methods. The disc-diffusion test was used to evaluate the antibacterial effect of the coating on Staphylococcus aureus, Staphylococcus epidermidis, and Enterococcus faecalis cultures. Samples with the antibacterial coating were implanted subcutaneously, and changes in the hematological and biochemical parameters of rat blood were studied in dynamics. Statistical data processing was performed using Tukey’s test, the Shapiro–Wilk test, the Kruskal-Wallis test, and the Mann- Whitney U-test. Results. In vitro experiments confirmed the presence of an antibacterial effect of the titanium blocks vancomycin-containing coating on cultures of Staphylococcus aureus, Staphylococcus epidermidis, and Enterococcus faecalis. The results in vivo experiments indicate that the hematological and biochemical parameters of rat blood before surgery, 2 and 4 weeks after implantation of titanium blocks are within the physiological norm. There were no statistically significant differences between the values of the control and experimental groups. The established value shifts reflect the body's response to anesthesia and surgery. Conclusions. Antibacterial coating for implantable medical devices made of titanium, which contain vancomycin, and polylactide-co-glycolide (50:50) has an antibacterial effect against Staphylococcus aureus, Staphylococcus epidermidis, and Enterococcus faecalis cultures. The results of the study of hematological and biochemical parameters of the control and experimental groups indicate that there is no toxic effect of the antibacterial coating of titanium blocks on the body.

The article describes surface hardening of aircraft engine titanium-alloy hydraulic cylinder face using the method of electro-spark doping by low-energy discharges. Graphite electrodes were used to provide functional behavior of the cylinder surface layer. The carbon oxide layer formed has a highly dispersed structure of a complex composition (with particles of titanium carbide, titanium oxide, graphite), 3-10 micron thick, characterized by high hardness and sliding properties. Graphite electrode alloying practically does not change the part dimensions. Subsequent diamond burnishing of the hardened surfaces decreases the value of the friction coefficient and surface roughness. Healing of defects and micro-cracks improves the fatigue resistance of the part. The developed technology makes it possible to assure the characteristics required of hydraulic cylinder work surfaces and increase their life.

Three-dimensional printing of porous titanium implants is a promising area of additive production in orthopedic surgery. The question remains relevant mechanical strength and durability of such device. Objective. Determine in the experiment the strength of the stem, the neck of the stem and the cups of hip endoprosthes made by 3D-printing from titanium alloy, and compare with a similar rate of serial implants. Methods. The strength of the stem and cups of hip endoprostheses made by 3D-printing on an Arcam printer from titanium alloy TI6AL4V was studied. Serials hip implants made form titanium alloy. There were 3 samples of hip endoprostheses for each test. Stems of endoprostheses were examined on the TIRATEST-2300 machine under the conditions of loading on a three-point bend, the necks of stems were examined under the influence of combined load on the bend with a shift, the cups were examined on compression. Results. Tensile strength in the case of three-point bending of the stems of implants made by mechanical processing and 3D printing did not have any differences significantly (p = 0.146) and was (1480.62 ± 62.50) MPa and (1396.88 ± 50.90) MPa, respectively. The necks of stems of serial endoprostheses and made by 3D-printing had a comparable limit of strength -- (408.61 ± 1.25) MPa and (403.49 ± 8.99) MPa, respectively (p = 0 .384). Under the conditions of compression tests of cups of endoprostheses all the samples withstood a load of 98.0 kN without any signs of destruction. Conclusions. The values of the tensile strength of the components of serial implants and those made by 3D-printing did not differ statistically significantly. Thus, 3D-porous structures have significant potential for creation of elements of hip endoprostheses. Key words. 3D-printing, additive technology, orthopedic implants, titanium alloy, hip arthroplasty, tensile strength of porous titanium structures. [ABSTRACT FROM AUTHOR]

Using the example of tests of two-phase sheet high-strength titanium alloys VT23 and VT23M with different initial structure and phase composition, the main regularities in the change of mechanical properties due to additional force impulse loading at room temperature are established. It is shown that dynamic non-equilibrium processes (DNP), which are realized in alloys under a given loading type, can lead both to a significant improvement of mechanical properties during subsequent static stretching, and to their deterioration. The factors influencing this process are analyzed.

Relevance of the work is caused by the need to improve the tribological characteristics of titanium alloys in order to expand their application. The main aim of the research is to study the regularities of wear of titanium alloys PT-3V and VT6 with coarse and ultrafine grained structure in friction with boundary lubrication; to identify the most significant parameters of ultrafine grained structure that influence wear resistance of alloys PT-3V and VT6; to determine the most optimal regimes of abc-pressing, ensuring the formation of ultrafine-grained structure with parameters increasing the wear resistance of alloys PT-3V and VT6. The methods used in the study: X-ray structural and phase analysis with radiation CoKα, optical metallography, methods of scanning and electron microscopy, electron microprobe analysis method, electron backscatter diffraction method (EBSD) using software CHANNEL 5. The results: the formation in alloys PT-3V and VT6 with ultrafine-grained structure by the methods of severe plastic deformation does not alter the adhesive wear mechanism of these alloys. The wear of alloys PT-3V and VT6 with coarse-grained and ultrafine-grained structure is the result of an adhesive transfer of samples material to a counterbody and formation of a large number of wear particles. When forming a highly nonequilibrium structure it is the nonequilibrium of the structure which has a decisive influence on its wear resistance.

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electrometallurgy Today / Sovremennaya Elektrometallurgiya is the property of International Association Welding (Paton Publishing House) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electrometallurgy Today / Sovremennaya Elektrometallurgiya is the property of International Association Welding (Paton Publishing House) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electrometallurgy Today / Sovremennaya Elektrometallurgiya is the property of International Association Welding (Paton Publishing House) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Presented are the results of the development of efficient technological processes of electron beam welding of beam structures of titanium VT-6 alloy with high resistance of welded joints to the formation of fatigue cracks, the diffuser of gas turbine engine of OT-4 alloy using slot welds, the chamber of medium pressure gas-turbine engine of VT5L alloy, providing a high accuracy of geometric dimensions. 5 Ref., 16 Fig. [ABSTRACT FROM AUTHOR]

Titanium pseudo-β alloys have high strength reaching 1200-1400 MPa in aged state as well as high fabricability in comparison with alloys with pseudo-α or (α+β) structure. Such advantages of pseudo-β-titanium alloys, typical representative of which is high-alloy VT19, make this class of titanium alloys perspective for application in new equipment and during modernization of existing one. The paper has studied the effect of mode of electron beam welding, modes of pre-heating and local heat treatment as well as furnace annealing on properties of welded joints of pseudo-β-titanium alloy VT19 produced by electron beam welding. Variation of rate of electron beam welding of alloy VT19 does not allow changing relation between α- and β-phases within the significant limits in weld metal and heat affected zone. Electron beam welding in combination with pre-heating allows regulating the relation between α- and β-phases in welded joint metal and reduce content of β-phase in weld metal of alloy VT19 from 91 to 53% as well as rise strength of welded joints from 876 to 937 MPa. [ABSTRACT FROM AUTHOR]

Copyright of Electrometallurgy Today / Sovremennaya Elektrometallurgiya is the property of International Association Welding (Paton Publishing House) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electrometallurgy Today / Sovremennaya Elektrometallurgiya is the property of International Association Welding (Paton Publishing House) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electrometallurgy Today / Sovremennaya Elektrometallurgiya is the property of International Association Welding (Paton Publishing House) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electrometallurgy Today / Sovremennaya Elektrometallurgiya is the property of International Association Welding (Paton Publishing House) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Problems of Friction & Wear is the property of National Aviation University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)