bluuebunny/crossref_metadata_2025 huggingface dataset:
Nickel-Based Slag-Remelted Superalloy for Ti-Alloys Isothermal Forging Die-Tool
Authors: Anishchenko Oleksandr S. , Kukhar Volodymyr V. , Klimov Eduard S.
Published: August 2021

The work purpose is to evaluate the application of nickel-based CrNi73CuBeTeAl superalloy (tungsten-free), made by electroslag remelting as a die tool material for isothermal forming. Isothermal deformation was simulated by tests for high-temperature cyclic creep. The specimens with high and × in plan dimensions (both parallel and perpendicular to the ingots central axis) were cut from the bottom, top and central zone, near the lateral surface and in the ingots central axis area. The tests were performed at 900, 940 and 980 °C constant temperature with 100, 200 and 300 MPa cyclic pressure in 0.02, 0.2 and 2.0 mm/s velocities range corresponded to 10-3-10-1 1/s strain rates. Such tools application field is compressor blades Ti-forgings die forging and sizing with ε = 1.0-3.0% residual upsetting deformation of dies during operation. It is shown that the die life can be extended to 400-700 loading cycles at 850-950 °C operating temperature and pressure up to 150 MPa.
Explosive Stamping Goals and Objectives Historical Transformation (to the 70th Anniversary of KhAI Scientific School)
Authors: Drahobetskyi Volodymyr V. , Taranenko Mykhailo E. , Kulynych Viktoriia D.
Published: August 2021

The sequence and development the impulse stamping goals and production objectives are described. A new idea development from a primitive “field” technology to modern integrated technologies that allow obtaining unique quality indicators of manufactured parts is shown. The article covers the description of pulse technologies for sheet stamping by the blasting agents explosion and an underwater high-voltage discharge.
Determining the Metal Corrosion Rate by Various Techniques and Comparison of the Results
Authors: Artamonova Inna V. , Gorichev Igor G. , Godunov Evgeny B.
Published: August 2021

The paper considers methods for calculating the rate of metals corrosion. A comparative analysis of the experimental data on the steel 10 corrosion rate in carbonate solutions with different pH values (6-12.5) and the concentration of carbonate ions on the disk electrode made of steel 10. The calculation of the corrosion rate by the gravimetric method and the method of polarization resistance is carried out. A detailed description of the calculating the corrosion rate stages index from experimental electrochemical data (I-E) obtained on the potentiostat IPC PRO is given. The advantages and disadvantages of the considered methods are indicated.
Predicting Strength of Titanium Alloys Using Aluminum and Molybdenum Equivalents at Operating Temperatures
Authors: Egorova Yuliia B. , Davydenko Lyudmila V. , Shmyrova Alisa V.
Published: August 2021

This study contains the results of statistical studies of strength of sheeted products and bars made from α-, near α-, and α+β titanium alloys based on their composition. Based on summarizing the literature data, we have studied the ultimate tensile strength after mill annealing of 30 serial and experimental alloys at testing temperatures between 20 and 600°C. We have also substantiated the possibility to evaluate the tensile strength of semi-finished products using the strength equivalents (such as aluminum and molybdenum) of alloying elements and impurities at various temperatures. We have put forth models that help to predict the ultimate strength of titanium alloys based on their composition and the operating temperature with a confidence level of 0.95 and statistical errors comparable with the regulated spread.
Structure and Phase Transformations in High Nitrogen and High Interstitial Steels of Different Alloying Systems - Short Review
Authors: Berezovskaya Vera V. , Merkushkin Eugeny A. , Mamchits Ksenia A.
Published: August 2021

The features of the structure evolution under thermal effect of Cr, Cr-Ni, Cr-Ni-Mn, and Cr-Mn-austenitic stainless steels with high nitrogen content and a total high content of carbon and nitrogen are analyzed. When studying the structure, we used light and electron microscopy, X-ray diffraction, dilatometry analysis and electrical resistance measurements. Fine structure and aging processes of austenite, nature and morphology of excess phases, as well as character of phase transformations and their relationship with the properties of steels have been studied. It is shown that Cr-Mn-steels with a high content of (C + N), having a homogeneous structure of austenite without excess phases, surpass Cr-Ni austenitic steels in mechanical and corrosion properties, have higher process ability than Cr-Mn-N-steel and are comparable with them in mechanical properties.
To the Issue of Low-Alloyed Copper Alloys for Contact Wires
Authors: Brusnitsyn Sergey V. , Gruzdeva Irina A. , Morgunov Vadim V.
Published: August 2021

This paper is about a comparative analysis of the requirements of the Russian standard, the standard of the European Union and the PRC for overhead contact wires for electrified high-speed railways. New generation contact wires must have a high level of mechanical, electrical and operational properties. The Russian standard does not regulate the chemical composition of alloys used for the contact wires manufacture. Unlike the standards of the European Union and China, the Russian standard regulates the maximum value of the relative creep. Compositions, mechanical properties, electrical resistivity and recrystallization temperature for the contact wires with a cross section of 120 mm2 are given. The requirements for the material for the contact wire are presented. The need to use more durable conductive materials instead of copper is noted since mechanical loads and operating temperatures are constantly increasing. The values of mechanical properties, recrystallization temperature and creep of contact wires made of copper alloys are given. Based on the analysis results of the literature data and the experiments, alloys of the Cu-Mg system are recommended as a material for the contact wire manufacture for an overhead network system for high-speed railways.
Specific Features of Statistical Analysis of Relative Grain Boundary Energies Obtained by Scanning Tunneling Microscopy
Authors: Stolbovsky Alexey V. , Murzinova Svetlana A.
Published: August 2021

An approach based on statistical analysis is proposed for the processing of data obtained using scanning tunneling microscopy of grain boundaries, which allows a numerical estimation of the relative energy of grain boundaries. The proposed statistical model also gives a possibility to separate groups of grain boundaries depending on their average relative energy and fraction in general distribution. Scanning tunneling microscopy data analyses have been carried out on data obtained by investigating copper and nanostructured copper were analyzed coarse-grain commercially pure copper and on copper nanostructured by the equal-channel angular pressing (ECAP) method. Obtained results were compared with available in literature experimental data for these types of materials, received by other methods. It is established that the grain boundaries in coarse-grain copper have significantly lower relative energy in contrast to the grain boundaries of ECAP-treated copper. Besides, there is, except for boundaries with high relative energy, a fraction of boundaries in the deformed sample with energy corresponding to those in coarse-grain copper.
Liquation and Crystallization Cracks in Aluminum Alloy AA2024 during Selective Laser Melting
Authors: Loginova I.S. , Popov N.A. , Solonin Alexey N.
Published: August 2021

In this work we studied the microstructure and microhardness of standard AA2024 alloy and AA2024 alloy with the addition of 1.5% Y after pulsed laser melting (PLM) and selective laser melting (SLM). The SLM process was carried out with a 300 W power and 0.1 m/s laser scanning speed. A dispersed microstructure without the formation of crystallization cracks and low liquation of alloying elements was obtained in Y-modified AA2024 aluminum alloy. Eutectic Al3Y and Al8Cu4Y phases were detected in Y-modified AA2024 aluminum alloy. It is led to a decrease in the formation of crystallization cracks The uniform distribution of alloying elements in the yttrium-modified alloy had a positive effect on the quality of the laser melting zone (LMZ) and microhardness.
The Repair of Defects in High-Manganese Steel Castings by Welding Technology
Authors: Berezovskiy Alexander V. , Shalimov Michael P. , Votinova Ekaterina B.
Published: August 2021

Welding technologies are used to repair defects in cast parts of high - manganese austenitic steel (Hadfield steel). These include repair welding for newly manufactured castings, welding the formed defects in the old operating cast parts and, finally, for cladding layer of wear-resistant metal on the surface of the cast parts. Manual metal arc welding (MMAW) are used as often as gas metal arc welding (GMAW) and of flux-core wire welding (FCAW-S). These welding processes make possible to obtain a weld metal with the expected quality of the restored surface and a slight distortion of the base metal structure. The article presents methods of the casting repair by welding and surfacing. The parameters of welding and surfacing procedures are given, welding materials are recommended, and the methods for nondestructive testing of welds are prescribed.
Mechanism of EDM Intensification at Ultrasound Application
Authors: Gruzdev Andrey A. , Morgunov Yuriy A. , Saushkin Boris P.
Published: August 2021

This paper considers some theoretical provisions on the impact ultrasonic mechanical vibrations have on the throughput of an electroerosive piercing of small-diameter holes. The approximate estimates confirm the hypothesis that the cumulative jets mechanism makes the greatest contribution to the intensification of a multiphase medium flow in the interelectrode gap. A model is proposed for a periodic localization of the cavitation region in the bottom part of the annular side gap. It allows explaining the occurrence of a multiphase medium flow during hole processing.
Simulation of Thermal Cooling Curves in the Process to Ordering Alloys by the Monte Carlo Method
Authors: Khalikov Albert R. , Dmitriev Sergey V.
Published: August 2021

An algorithm is proposed for constructing curves of thermal cooling and ordering kinetics with a monotonic decrease in temperature for alloys to stoichiometric composition. Modeling is carried out by the Monte Carlo method in the model of a rigid crystal lattice and pair interatomic interactions. The application of the algorithm is illustrated by the example to a square lattice, taking into account interatomic interactions in the first two coordination spheres for alloys with the composition AB, A3B, and A3B5. The proposed model makes it possible to calculate individual sections of the phase diagrams to the state for binary alloys.
Use of Lebedinsky Mining and Processing Works Overburden Chalkstone for Iron-Ore Pellet Fluxing
Authors: Yur'ev Boris P. , Matiukhin Vladimir I. , Dudko Vyacheslav A.
Published: August 2021

Mine rocks generated abundantly in the course of iron-ore deposit development and containing high quality overburden chalkstone are mainly stored in dump pits. This relates to the Lebedinsky Mining and Processing Works as well. This results in certain environmental issues. Therefore the work provides the investigation results in some measure allowing the defined problem solution through complete replacement of limestone used for iron-ore pellet fluxing by the overburden chalkstone. This required a whole set of experiments.
Derivatographic investigation was carried out on the overburden chalkstone samples of the Lebedisky Mining and Processing Works and allowed defining of the studied sample temperature and heating time impact on production of chalkstone with varying decarbonization process extent. Activity of the lime produced from the chalkstone was evaluated through determination of the total content of active calcium and magnesium oxides in it. In the course of the experiments the temperature and time impact on the liming process was defined. To justify the potential of the overburden chalkstone use as an additive for iron-ore pellet fluxing and their production with sufficiently high strength properties ensured, as well as of the complete replacement of the limestone used for these purposes, the experiments with the briquettes were carried out. At that the briquette composition complied with that of the fluxed iron-ore pellets. The briquette strength properties with chalkstone additives versus the firing temperature and degree were studies, as well as physicochemical processes occurring in the samples at their heat treatment. As a result of the investigation it was determined that the chalkstone additive use in the pellet fluxing contributes to their significant strength increase.
The obtained results are of certain interest for the specialists dealing with iron ore material preparation for metallurgical conversion and allow development of pellet heat treatment conditions ensuring their high metallurgical performance.
Thermal Analysis of Al-5Ti1-1B Ligature
Authors: Cherepanov Aleksandr I. , Kukartsev Viktor Alekseevich , Tynchenko Vadim Sergeevich
Published: August 2021

At present, casting and wrought high-strength and light aluminum alloys are widely used in the creation of a number of products and units in mechanical engineering, aviation and space technology. The process of developing alloys includes the formation of initial design data covering the operating conditions, the necessary physical, mechanical and other characteristics of products, and also considers the requirements of manufacturability in their manufacture and ensuring a given structure. To achieve these goals, when smelting aluminum alloys, Al-Mg, Al-Cu, Al-Mn, Al-B, Al-Ti ligatures are used. Despite the widespread use of ligatures, there is no single set of requirements for their quality. However, recent studies in the field of structural heredity in the "charge - melt - cast product" system have shown that the structure of the ligature has a significant hereditary effect on the crystallization process, structure and properties of the modified alloy. In this work, a study of the Al-5Ti-1B master alloy was carried out using synchronous thermal analysis, which made it possible to establish such properties as: the magnitude of the thermal effect, the temperature of its onset, enthalpy, and the crystallization interval. The results obtained make it possible to expand the bank of initial data to improve existing programs for modeling casting processes and to develop new ones.
Methodology for Evaluation of Treated Steels and Alloys in Abrasive Processing
Authors: Shumyacher Vyacheslav M. , Kryukov Sergey A. , Baidakova Natal'ya V.
Published: August 2021

One of the critical physical and mechanical properties of metals and alloys is the suitability for abrasive machining. Machining by abrasive tools is the final operation that sets the desired macro-geometry parameters of processed blanks and microgeometry parameters of processed surfaces such as roughness and length of a bearing surface. Abrasive machining determines the most important physical and mechanical parameters of a blank surface layer, i.e. stresses, phase composition, structure. Machinability by abrasive tools depends on the machining performance affected both by the blank material properties and various processing factors. In our previous studies, we proved that during abrasive machining the metal microvolume affected by abrasive grains accumulates energy. This energy is used for metal dispersion and is converted into heat. According to the theoretical studies described herein, one may note the absence of a reliable and scientifically valid method as well as measuring instruments to determine the machinability of metals and alloys by abrasive tools. For this reason, we suggested a method simulating the effect the multiple abrasive grains produce in a grinding wheel, and enabling us to identify machinability of metals and alloys, select the most efficient abrasive materials for machining of the same, and form the basis for development of effective grinding operations.
Investigation of Uneven Properties of Stainless Steel 12Kh18N10T Depending on the Thickness of the Sheet
Authors: Tipalin Sergey A. , Belousov Vladislav B. , Shpunkin Nikolay F.
Published: August 2021

The authors conduct the research of the properties of a cold-rolled sheet made of corrosion-resistant steel 12Kh18N10T of a variable thickness. Further, they build hardening curves and defined their coefficients. The research identifies the patterns of the thickness impact on the nature of hardening of the sheet material 12Kh18N10T. The authors conduct the measurements of micro-hardness along the sheet thickness. The article confirms the suggestion that hardness in the sheet center decreases for various thicknesses. The authors further present a comparative analysis of hardness values distribution for the corrosion-resistant steel 12Kh18N10T and steel containing 0.08% of carbon. It is revealed that lower material thickness alters the strength parameters of the process and increases the mean material hardness. The authors provide the hardening curves for various sheet thicknesses and the dependence of hardness distribution on the thickness of these sheets.
The Formation Energy of Martensite Nuclei and the Phase Transition Kinetics under the Action of an External Magnetic Field
Authors: Pustovoit Viktor N. , Dolgachev Yuri V.
Published: August 2021

The formation energy of martensite nuclei in the austenite matrix is calculated. Nanoclusters with ferromagnetic order, which exist in austenite above the Curie temperature, reduce the formation energy of a critical martensite nucleation center when exposed to an external magnetic field. The data obtained are explained by the magnetic separation of the initial phase under the action of a magnetic field. A fluctuation increase in nanovolumes with a ferromagnetic order in austenite increases the energy in a atoms group of the matrix phase with a parallel spins arrangement. As a result, the nucleation rate of the martensite phase increases and the martensitic transformation proceeds more completely.
Investigation of the Influence of Ultrasound Action on Diffusion Processes in an Explosion-Welded Bimetal System Cu-Al during Heat Treatment
Authors: Slautin Oleg V. , Pronichev Dmitriy V. , Kuz’min Evgeniy V.
Published: August 2021

The influence of ultrasound on the main regularities of the formation and growth of the diffusion zone at the interlayer boundary of an explosion-welded layered composite material of Al-Cu systems is investigated. It is proved that the effect of ultrasound contributes to the reduction of the latent period of the nucleation of intermetallic phases at the interlayer boundary, lowers the temperature of the beginning of the eutectic transformation (by about 10 ° C), but at the same time does not affect the phase composition of the diffusion zone as a result of homogeneous reactions at the boundary of contact of solids. It has been established that the thickness of the diffusion zone, with the duration of the supplied acoustic vibrations, ensures the absence of cracks in the diffusion zone, leading to delamination of the material, increases by 30-40% at a fixed temperature of intense diffusion.
Regularities of the Influence of Substitutional and Interstitial Alloying Elements on the Corrosion Properties of Austenitic Stainless Steels
Authors: Merkushkin Eugeny A. , Berezovskaya Vera V. , Serzhanin Mikhail A.
Published: August 2021

Pitting corrosion studies were carried out on nitrogen containing austenitic stainless steels of different compositions and concentrations of alloying elements. As was shown there is a certain predicted influence of the concentration of each alloying elements as chromium, manganese, nickel, carbon and nitrogen on the pitting potential (Eb) of investigated steels with the nitrogen content less than 0.169 wt. %. However with an increase of the nitrogen content to a certain value (in our study up to 0.82 wt. %) the predicting of alloying elements influence on pitting potential of the steels requires a new approach. Based on the analysis of the experimental results and to take into account the influence of all alloying elements in steel on the pitting potential, a regression equation is proposed. In the presence of nitrogen, the positive role of carbon on the pitting resistance of stainless steel was shown, and the critical values of the total content (C + N) and the C / N ratio were determined, allowing prediction of the best composition of stainless steel.
A Study of the Influence of Local Heat Treatment on the Structure of Welded Titanium Pipelines
Authors: Astafeva Natalia A. , Balanovskiy Andrey A. , Pershina Anna A.
Published: August 2021

The article analyzes the results of a study of the influence of zonal heat treatment on the structure of welded joints of pipeline elements made of titanium alloys Ti-3.5Al-1.5Mn. In the manufacture of such structures, the TIG welding method is used to join pipe elements, after which the heat treatment method can be used to relieve residual stresses. The experiments have confirmed the effectiveness of zonal heat treatment preceded by welding. It was revealed that for welded joints made of titanium alloys, heat treatment can stabilize the structure. In experiments conducted by the method of optical metallography, the structure of heat treated and untreated welded joints was investigated. The influence of heat treatment on the weld structure and heat-affected zone was identified.
To the Issue of Mathematical Modeling of the Red Mud Thickening Process
Authors: Salamatov Victor I. , Salamatov Oleg V. , Zabolotnyaya Daria Yu.
Published: August 2021

The article focuses on the main mathematical modeling principles for engineering processes. The physical model of the red mud thickening process has been formed. The choice of mathematical model type has been described where the mathematical model represents the physicochemical character of the thickening process and allows estimating pulp water-yielding features at the stage of compression. Mathematical modeling of the engineering process, based on the studies of physicochemical patterns in its course and consideration of these patterns in the mathematical model, does not have certain disadvantages. Experimental data, used at the mathematical model formation where the mathematical model represents the physicochemical mechanism of the process, serve for their further analysis, physicochemical and mathematical interpretation. The mathematical model should be used as a method for detecting internal patterns in the process and for identification and quantitative assessment of its features.
Truck Synchronizer Rings Recovery by Plastic Deformation Technology
Authors: Pankratov Dmitriy L. , Shaparev Alexander V.
Published: August 2021

A truck's gearbox friction rings restoring process by hot 3D stamping was developed and adopted for implementation. Using this recovery method in combination with subsequent synchronizer rings mechanical processing allows restoring up to 95% resource of worn parts. It was established that section of a stamp's deforming element for axisymmetrical parts restoring should be a one-way wedge with a sloping face facing the reconstructed surface. The most significant factors influencing the transmission gearbox synchronizer rings restoring process are: stamp deforming element thickness, plunging depth and distance to a recoverable surface. The energy and force parameters study of hot plastic deformation process serves as input data for automatic design systems of working elements of stamps for restoring synchronizer rings as well as for determination of a required deforming force during hot stamping.
Granulometric Characteristics Study for the Particles of the Cu2-xS - Fex+1S System
Authors: Nechvoglod Olga Vladimirovna , Sergeeva Svetlana V. , Abaturov Ivan S.
Published: August 2021

The electrolysis of granular matte is a new alternative method for processing sulphide copper materials with the production of cathode copper and the conversion of sulfur to the elemental state. For the first time were established the regularities for the Cu2-xS – Fex+1S granules distribution by the size classes of obtained granulations for the Cu - Fe - S melt at temperatures of 1200, 1250, 1300 and 1350 °C. The maximum amount of Cu2-xS – Fex+1S material of size class 5.0 + 2.5, -2.5 + 1.6 and-1.6 + 1.0 mm, which corresponds to the conditions of following electrochemical processing and estimated as 72.5%, was obtained by granulation of the melt at 1200 °C. The granulometric characteristics of Cu2-xS – Fex+1S granules were estimated. With an increase in the overheating temperature of the Cu - Fe - S melt, granules with a large value of the average diameter were obtained, also the root-mean-square deviation of the particle size from the average value increases and the degree of polydispersity of the granules decreases. The duration of cooling for Cu2-xS – Fex+1S granules from the melt temperatures at 1200, 1250, 1300 and 1350 °C was calculated. In the entire considered temperature range, the particle cooling time is much longer than the spheroidization time, which contributes to the formation of spherical particles.
Targeted Alternation in Properties of Solid Amorphous-Nanocrystalline Material in Exposing to Nanosecond Laser Radiation
Authors: Safronov Ivan S. , Ushakov Alexander I.
Published: August 2021

One of the most important purposes of materials science is the ability to govern the physical properties of materials characterized by different structures. The strength properties of nanostructured metal alloys do not always meet the exploitation requirements. The set of properties of such materials is stable within narrow limits: temperature, mechanical, and corrosion conditions. Traditional processing modes are ineffective for such materials. Attempts to use them often lead to the loss of unique physical and chemical properties. The most effective methods of processing such materials are associated with the use of laser radiation. The laser pulse has a number of features, including a complex effect on the surface layers of the material. Spot and short irradiation with high-energy rays can preserve the unique physical properties of samples as a whole and improve strength indicators without destroying the structure of the material as a whole.
Multiple Reflow Influence over the FeCoCrAlTiCuNiMo Coating Obtained by Plasma Metallization on its Wear Resistance under Dry Friction
Authors: Kadyrmetov Anvar M. , Popov Dmitri A. , Snyatkov Yevgeny V.
Published: August 2021

The article presents the research results of the plasma jet multiple reflow effect over the multicomponent coating FeCoCrAlTiCuNiMo, obtained by plasma metallization in an open atmosphere, on its wear resistance under dry sliding friction. The research results indirectly confirm the influence of the coating entropy over the wear resistance increasing along of the reflow number growth.
The Principle of Choosing the Composition of the Protective Coating for Die Casting Molds
Authors: Gavariev Renat V. , Gavarieva Ksenia N.
Published: August 2021

The article considers the requirements for protective coatings operating in the conditions of injection molding of non-ferrous metal alloys, among which the most important are the provision of crack resistance and wear resistance of the forming surface. It is revealed that single-layer coatings applied by the physical vapour deposition method, regardless of its composition, are not able to fully meet the formulated requirements. It is established that multilayer coatings provide increased performance of structural elements of molds in comparison with single-layer ones.
Application of Multi-Element Targets for the Formation of High Entropy Coatings
Authors: Eremin Evgeniy N. , Guchenko Sergey A. , Yurov Viktor M.
Published: August 2021

The development of modern technologies in various industries cannot be imagined without the development and use of new materials, including new highly entropic alloys (HEA) and coatings based on them, as more advanced in terms of performance compared to traditional materials and coatings. Methods for producing various highly entropic alloys are described in many literature. Almost all such technologies at the moment cannot be applicable in the mass production of parts due to the high cost and lack of appropriate infrastructure and production technologies. However, obtaining coatings formed on the basis of highly entropic alloys for various parts of mechanisms and machines is currently a highly promising direction in improving the operational properties of work surfaces. The goal of this work is to create highly entropic coatings obtained by magnetron sputtering of special multicomponent targets. The paper shows the possibility of synthesis of coatings of the predicted composition and properties. A coating based on a matrix target made of 12Kh18N10T steel with pressed multicomponent Cr-Ni-Zr-Ti-Cu pellets was synthesized. The elemental composition of the coating and its properties were determined, the microhardness was measured, and the functional properties were established.
Heat Resistance of Steel N8G6M3FTB Obtained by Surfacing Cored Wire
Authors: Eremin Evgeniy N. , Losev Alexsander S. , Borodikhin Sergey A.
Published: August 2021

The operational reliability of rolling production tools depends on the heat resistance of the steel from which they are made. To increase the performance of the rolls, a hardening surfacing with wear-resistant alloys is used. The effectiveness of the applied hardening technology depends on the functional characteristics of the deposited metal. The aim of the work is to study the tempering resistance in the state after heat treatment of the deposited steel (Fe-C-Ni-Mn-Mo-V-Ti-Nb system). It was established that the thermal resistance coefficient of steel 15N8G6M3FTB at temperatures from 650 to 800 °C varies from 0.76 to 0.66, which exceeds the heat resistance of steel 30Kh2V8F by 1.5 times. It is shown that in the fine structure of such a metal after tempering at 800 °C, large amounts of finely dispersed precipitates are observed. These precipitates have a rounded shape up to 100 nm in size and belong to the Laves phases - Fe2Mo, Fe2Nb, and Fe2Ti. The obtained high heat resistance values of 15N8G6M3FTB steel make it possible to recommend it for creating surfacing materials. Flux-cored wire based on this steel can be used for hardfacing hardening of tools operating at temperatures up to 800 °C inclusive.
Modification of Titanium Surface by Ion Implantation
Authors: Legky Aleksandr D. , Zlobin Vladimir N. , Kudashev Aleksey S.
Published: August 2021

The article considers a method for obtaining deuterium storage on titanium samples. The depth of penetration of deuterium ions into the outer surface of porous titanium is calculated by increasing the resistance of the samples. Higher resistance of the samples is shown to be caused by the creation of a dielectric layer of titanium deuteride on the surface. It was proven that the depth of penetration of deuterium ions into the surfaces of the samples is significantly greater than the classical concept about the doping process explains. The design of an ion doping unit contains a vacuum working chamber with a working table for placing samples. The ion beam comes from an ion source in crossed electric and magnetic fields of the Penning type. The working gas of the ion source is deuterium. The ion source gas is supplied through a special fitting in the design of the ion source, connected to the deuterium cylinder through a special leak. The working chamber is pumped out by a high-vacuum unit, to which a pre-vacuum pump is connected at the outlet. The ion implantation unit is electrically powered from three power sources. A power supply with a voltage of up to 5 [kV] and a current of up to 100 [mA] feeds the gas discharge of the source. The 10 [kV] power supply gives a negative potential to the target, and deuterium ions coming out of the hole in the cathode of the ion source are accelerated towards the desktop with the power supply up to 40 [kV] and up to 10 [ma].
Evaluation of the Heat Resistance of the Fe-Cr-Al System Coatings
Authors: Kulevich Vitaliy P. , Slautin Oleg V. , Kharlamov Valentin O.
Published: August 2021

The influence of the chemical composition of aluminide coatings of the Fe-Cr-Al system on their heat resistance at 1100 °C was investigated. It is shown that the lowest oxidation rate is possessed by the coating obtained by aluminizing the Cr15Al5 alloy in the silumin melt, for which the depth of corrosion penetration after 500 h at 1100 °C did not exceed 2.5 μm. The depth of corrosion penetration after 500 h at 1100 °C in coatings with a higher chromium content (23 at.%) reaches 8.9 μm. A decrease in the content of chromium (up to 5 at.%) or aluminum (up to 10 at.%) in the surface layer is accompanied by a critical increase in the corrosion rate. The longest time of retention of heat-resistant properties at 1100 °C is possessed by the coating obtained by aluminizing the Cr23Al5 alloy in an aluminum melt.
Effect of Coatings on the Performance of Injection Molds
Authors: Gavariev Renat V. , Soldatkina Elena N. , Gavarieva Ksenia N.
Published: August 2021

It is known from theory that coatings on the forming surface increase the service life of injection molding molds. In practice, the most widespread method of nitriding, which has a number of undeniable advantages, while there are other promising coatings. Therefore, the article considered coatings applied by the physical vapour deposition method in comparison with nitriding. The comparison was carried out on the basis of pressure and temperature indicators on the walls of the forming surface of the working inserts of the molds.
Effect of Heat Treatment on the Structure and Properties of the Carburized Layer of the Legs of Three-Ball Drill Bits
Authors: Petrova Olga N. , Belikov Sergey V. , Slukin Yuri V.
Published: August 2021

The effect of time-temperature parameters of heat treatment on the structure and properties of carburized case and the core of 19CrMnNiMo steel was studied. The critical points were determined by dilatometric analysis: Ac1 = 740°C, AC3 = 835°C. It was established, that after carburizing at 940 °C, prequench to 890 °C with oil cooling, quenching at 790 °C and tempering at 180 °C, martensite structure of carburized case with uniformly distributed carbides and the least amount of retained austenite is formed. The hardness of carburized case decreases smoothly from the surface into the depth, in proportion to the decrease in the carbon concentration and amounts to 60-50 HRC. The technological process of heat treatment of drill bit legs made of 19CrMnNiMo carburized steel providing minimal amount of retained austenite in structure, absence of carbide network and combination of optimum mechanical properties which is proved by a real on-site experiment is developed. Temperature conditions of carburizing, quenching and low tempering are recommended for the production of legs of roller bits.
Confirmation of Hydrogen Embrittlement Mechanism for Stress Corrosion Cracking of Gas Main Lines
Authors: Volgina Natalya I. , Shulgin Aleksander V. , Khlamkova Svetlana S.
Published: August 2021

The nature and mechanism of stress corrosion cracking have been studied and modeled in laboratory conditions. It was established that the destruction process develops in three stages: the formation of corrosion defects on the pipe surface, birth and subcritical growth of stress-corrosion cracks, and break. Release bands observed in focal fracture at subcritical crack growth stage indicate that fluctuating stresses are involved in the destruction development. Transcrystalline nature of the fracture at subcritical growth stage implies that SCC in pipelines develops in consonance with the hydrogen embrittlement mechanism.
Modeling Mechanical Properties of Multilayer Coatings TiAlN
Authors: Kolesnikov Vladimir I. , Suvorova Tatiana V. , Belyak Olga A.
Published: August 2021

The paper outlines two approaches (the ANSYS finite element modeling and the differential scheme of the self-consistency method) to model the mechanical properties of TiAlN multilayer coatings. To validate the experimental results, these findings were compared with the nanoindentation test results for single and multilayer coatings. This work has revealed the effect of Ti/Al ratio on the mechanical properties of multilayer coatings. The given approaches could be applied to calculate, with an acceptable margin of error, the mechanical properties of TiAlN multilayer coatings.
Studies of the Influence of High Temperatures and Aggressive Media on the Performance Properties of O-Rings Used in the Automotive Industry
Authors: Shakirova Gulgena D. , Romanova Natalya V. , Shafigullin Lenar N.
Published: August 2021

The paper provides the results of the studies on the influence of high temperatures and aggressive media on the performance properties of O-rings having one name but made by different manufacturers. O-rings by supplier No. 1 are made from fluorosilicone rubber, and O-rings by supplier No. 2 are made from fluororubber. The analysis of O-rings showed that the color of O-rings made from fluorosilicone rubber changed and their physical mechanical properties decreased after operation when subjected to G-energy Si-OAT and G-energy SNF coolants. The comparative analysis of TGA curves of O-rings showed that O-rings made from fluororubber were more heat stable than O-rings made from fluorosilicone rubber, i.e. they can withstand higher operating temperatures in an air atmosphere. Fluoroelastomers can recover quickly and are used to manufacture products which should have a high heat resistance during operation and high resistance to aggressive coolants.
Research of the Mechanical Properties of the Filament from the Percentage of Filling when Prototyping Machine Parts
Authors: Gryadynova Elena N. , Gorin Andrey V. , Rodichev Alexey Yu.
Published: August 2021

The article contains the analysis of thermoplastics used in prototyping machine parts. We used several types of experimental samples with different filling percentages. The equipment on which the experimental studies were carried out is shown. During the experiment, a specialized tensile testing machine was used. The experimental samples were installed in the developed centering device. Normal conditions were observed during the tests. The results of an experimental tensile study of PLA-plastic specimens are presented. The typical stress-strain diagram of an experimental sample is described, which describes the dependence of stress on relative deformation. An equation of the linear dependence of the tensile strength on the percentage of filament filling has been compiled, which makes it possible to determine the tensile strength of the product at any percentage of the filling of the plastic filament. The assessment is adequately verified by Fisher's criterion. Recommendations for filament filling in prototyping machine parts are given.
Enhancing Mechanical Properties of Various Sintered Pellets with Nano-Additives
Authors: Nguyen Tien Hiep , Konyukhov Yury V. , Nguyen Van Minh
Published: August 2021

The impact of Fe, Co, Ni nano-additives on the density, microhardness and bending strength was investigated for several sintered pellets. Fe, Co, Ni nanopowders (NP) were prepared in the size range 67-94 nm using chemical metallurgy techniques. These powders (0.5 wt. %) were dispersed into three sets of micron powders: Co (+0.5 wt. % Co NP); Fe (+0.5 wt. % Fe NP); Fe+0.5wt. % C (+0.5 wt. % Co and 0.5 wt. % Ni NP). Mixtures were further mixed and processed using a magnetic mill and a turbulent mixer. Sintering was carried out using spark plasma sintering (SPS) as well as pressureless sintering (PS). The densities of sintered pellets were found to increase by 2.5-3% (SPS) and 3-5% (PS) in the presence of nano-additives; corresponding increases in microhardness and bending strength were determined to be 7.9-11.1% and 17.9-38.7%, respectively. These results are discussed in terms enhanced packing due to interparticle sliding and the filling of free spaces with the nanodisperse phase.
Mathematical Model for Determining the Colorimetric Characteristics of Composite Materials Based on PLA and Wood Filler
Authors: Sabirova Gulnaz A. , Safin Ruslan R. , Galyavetdinov Nour R.
Published: August 2021

The environmental concern of many countries seeking to conserve natural resources is driving the development, production and consumption of biodegradable composites. However, in view of their high cost, adding various fillers to composites (such as, wood flour (WF)) is promising. The advantages of using composites with wood fillers are resistance to weathering, environmental friendliness, ease of mechanical processing, and the possibility of waste disposal. To improve the properties and expand the scope of such composites, it is possible to use thermal modification of the filler, which gives wood such properties as: high hardness, water resistance, chemical and biological resistance. Thermal modification consists in heating wood in the temperature range from 150 to 230 °C without oxygen. At the same time, color properties of the material are changed definitely: an increase in the processing temperature affects darkening of wood, which leads to a change in the color characteristics of the last composite. In this regard, a regression mathematical model is proposed for easy color control prediction of the product, which is obtained as a result of composites color analysis based on polylactide (PLA) and the RGB color code. The proposed mathematical model, setting the processing temperature of wood filler, lets predicting the intensities of red, green and blue components for the subsequent visual representation of the last composition color using standard computer programs.
Composite Membranes with a Cellulose Acetate Working Layer on a Nylon Substrate
Authors: Fazullin Dinar D.
Published: August 2021

Membrane technologies are currently among the most demanded. This is evidenced by their variety and a wide range of membrane applications in the most topical areas of human life. This work proposes a simple and inexpensive method for producing composite membranes for ultrafiltration and nanofiltration with a surface layer of cellulose acetate for water purification and water treatment processes. A nylon microfiltration membrane was used as a membrane base. The surface layer was obtained by immersion in a solution of cellulose acetate in acetone. Composite membranes with different retention properties were obtained depending on the number of deposited layers. The resulting membranes were examined for total porosity, water absorption, cellulose acetate content, contact angle, and IR absorption spectra. The specific productivity of the obtained membranes with respect to distilled water was also established.
On Question of Metals’ Plasticity
Authors: Shinkin Vladimir N.
Published: August 2021

Straightforward and reverse descriptions are used to describe the metal’s plasticity zone. For the straightforward descriptions of the hardening zone, the “reference” point is the relative deformation εy corresponding to the yield strength σy. The deviation of the relative deformations in the metal hardening zone is measured relative to εy, and the deviation of the normal stresses is measured relative to σy. For the reverse descriptions of the metal hardening zone, the “reference” point is the relative deformation εu corresponding to the ultimate strength σu. The deviation of the relative deformations in the metal hardening zone is measured relative to εu, and the deviation of the normal stresses is measured relative to σu.
Ozone Resistance of Vulcanizates Based on XNB Rubber
Authors: Bochkarev Evgeniy S. , Vostrikov Dmitriy S. , Tuzhikov Oleg O.
Published: August 2021

The paper represents ozone resistance of rubbers based on carboxylated nitrile butadiene rubber cured with epoxy resins and magnesium oxide. Ozone resistance was investigated using the express-method at a flow rate of the ozone-air mixture of 9 l/h and ozone content of 9 mg/l. In the method used, the “time to cracking start” indicator was taken as the basic indicator of ozone resistance. The second indicator characterizing the ozone resistance of elastomeric materials was the "rate of destruction" in the main period of destruction. There has been evaluated the effect of dissolved polyvinyl chloride in epoxy resin ED-20 on the properties of vulcanizates. There has been investigated the Increase in destruction time under the action of ozone.
Structure and Phase Composition of Ceramics Made of Powder Obtained by Chemical Dispersion of V95 Alloy
Authors: Nechaev Dmitriy A. , Omarov Asif Yu. , Ivanov Nikolay V.
Published: August 2021

The paper presents the results of differential scanning calorimetry, powder thermogravimetry, scanning electron microscopy, and X-ray phase analysis of ceramics made of powder obtained by chemical dispersion of B95 alloy. The process of obtaining a new ceramic material is briefly described. The mechanism of formation of the microstructure observed is described using the results obtained.
Magnetic Study on Divalent Ion Substituted Barium Hexaferrites
Authors: Vinnik Denis , Mahadevan Santhoshkumar , Sharma Puneet
Published: August 2021

Magnetic properties of Co, Ni and Zn substituted barium hexaferrite (BaM) samples prepared by solid state ceramic method were studied. Saturation magnetisation were found higher for Zn-substituted BaM, whereas, coercivity is higher for Co2+ and Ni2+ ion substituted samples. Anisotropy field for all substituted samples was calculated by the law of approaching saturation. Remanence, squareness and thermomagnetic plot suggest Zn2+ ions restricts the magnetic interaction of various sites in BaM.
Features of Melt Droplet Formation during Electrical Destruction Aluminum Films on the Semiconductor Surface
Authors: Koryachko Marina V. , Pshonkin Danila E. , Skvortsov Arkady A.
Published: August 2021

The work is devoted to processes during melting of thin aluminium film on silicon surface in pulse current mode. An experiment was conducted to study the dynamics during the onset of the liquid phase on a metal film. Besides, the process of formation droplet localization zones is considered. The experimental part revealed critical current values ​ during an electrical explosion of thin metal films near the thermal shock source. Using the oscillographic method, the temperature profile of the metallization track is calculated.
Influence of Laser Radiation on Movement of Dislocations in Silicon Single Crystals
Authors: Solovyev Alexander A. , Rybin Vladislav V.
Published: August 2021

The behavior of linear defects in n-and p-type silicon, generated by laser radiation is studied for pulse energy density 417 – 1083 mJ/cm2. The features of the nondestructive and destructive effects of the laser pulse on the surface defects formation of the semiconductor crystals are revealed. The formation and movement of dislocations in the crater region and the development of micro cracks, accompanied by acoustic waves are revealed.
Hyper-Pressed Composites from Recycling Products of Aerated Concrete Waste
Authors: Beregovoi Vitaly A. , Beregovoi Aleksandr M.
Published: August 2021

A technology has been developed for obtaining wall materials by the hyper-pressing method, including the recycling of large-tonnage waste from the production of autoclaved aerated concrete. The main component of the raw mixture is finely ground filler fractions, obtained by crushing substandard fragments of aerated concrete. The joint influence of raw mixture, the parameters of pressing and the conditions of hardening on the indicators of material properties has been investigated. There was given a quantitative assessment of the individual components contribution of the raw material composition to the indicators of the physical and mechanical properties of the material. The mechanism is disclosed of the constructive effect of aerated concrete recycling waste and plasticizing additives on the water resistance and strength of samples. The promising areas of application of hyper-pressed materials in modern construction are presented.