Proceedings of the Southwest State University. Series: Engineering and Technology最新文献

{"title":"Ionization processes of negative corona discharge. Part 2. Theory. Comparison with experiment","authors":"A. I. Zhakin, A. E. Kuzko","doi":"10.21869/2223-1528-2024-14-2-122-141","DOIUrl":"https://doi.org/10.21869/2223-1528-2024-14-2-122-141","url":null,"abstract":"   The purpose of the research is a theoretical analysis of ionization processes in the air, which are initiated by a high-voltage field generated by the negative needle-flat electrode electrode system.   Methods. Fe, Cu, Al electrodes are used. Calculations are carried out using the methods of quantum mechanics and mathematical physics.   Results. The processes of cold and thermoelectron emission of electrons, enhanced by an external high-voltage field (Schottky emission), are analyzed. The conditions under which the generation of charges from the cathode surface due to plasma-chemical reactions and the capture of surface electrons by electronegative oxygen molecules are decisive are investigated. Based on the PE theory, a theory of injection of negative ions from the cathode into an electronegative gas is constructed and the theory is compared with experiment. It has been shown that at small radii of curvature of needle tips, when E ≥ 106 V/cm, the generation of charges is due to cold emission of electrons. In average fields E ≈ 105 V/cm, electron emission is due to the Schottky effect. In fields E ≈ 104 V/cm and below, injection is caused by electrochemical processes and PE capture. A theory has been developed for PEs that appear at electric field intensities on the electrode of the order of several tens of kV/cm, that is, on flat and slightly curved negative electrodes. The capture of PE by electron-withdrawing molecules causes an injection current and, as a consequence, the ignition of a corona discharge. Analytical expressions for the surface density as a function of the local electric field strength, as well as an expression for the injection current, are obtained. The agreement between theory and experiment is satisfactory.   Conclusion. An analysis of the development of CR on negative needles is given. A theory of PE at the cathode in strong electric fields was developed. Based on the results of measuring dark negative current-voltage characteristics, it is possible to determine the patterns of surface processes involving electronic transitions, in particular, determine the concentration of PE and injection currents.","PeriodicalId":117184,"journal":{"name":"Proceedings of the Southwest State University. Series: Engineering and Technology","volume":"1 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141684340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Behavior of magnetic systems of different dimensions in a magnetic field","authors":"E. Shel'deshova, E. V. Bondar, I. A. Shabanova, A. Churaev, E. A. Sokolov, K. A. Matarykin, P. Ryapolov","doi":"10.21869/2223-1528-2024-14-2-142-155","DOIUrl":"https://doi.org/10.21869/2223-1528-2024-14-2-142-155","url":null,"abstract":"   Purpose. To investigate the influence of the magnetic field on the formation of structures in magnetic media of various dispersities.   Methods. Experiments to study the dynamics of magnetic inclusions were carried out on a self-made installation in flat transparent cells by microscopy. The magnetic field was created by an electromagnet FL-1 connected to a power source. Magnetite particles of various sizes, as well as metal balls with a diameter of 0.5 mm, were studied as a magnetic medium. Video recording was performed using a MICMED WiFi 2000X 5.0 microscope.   Results. The dynamics of magnetic inclusions in a viscous liquid medium under the influence of a magnetic field, as well as under conditions of mechanical shear effects, have been studied. The influence of the magnetic field strength on the growth rate of chain structures, as well as on the angle of deflection under shear action, has been studied. A theoretical interpretation of the observed phenomena is proposed.   Conclusion. During the experiment, it was found that under the influence of a magnetic field, magnetic inclusions form chain structures. Their size, growth rate and dynamics depend on the physical parameters of the system and the external magnetic field. An intensive increase in the formation of chains of magnetic inclusions was detected at low and medium values of the magnetic field strength. An experimental dependence of the angle of deviation of chain structures from the equilibrium position on the magnetic field strength is obtained, which correlates with known theoretical data, on the basis of which a computational model is proposed. The results of the study can be used to visualize numerical calculations of the dynamics of dispersed systems under external influences.","PeriodicalId":117184,"journal":{"name":"Proceedings of the Southwest State University. Series: Engineering and Technology","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141687208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of Copper nanoparticles obtained in AOT reverse micelles using flavonoids as a reducing agent","authors":"Javid Rashidi, L. S. Ageeva, E. A. Fatyanova, N. A. Borsch","doi":"10.21869/2223-1528-2024-14-2-168-179","DOIUrl":"https://doi.org/10.21869/2223-1528-2024-14-2-168-179","url":null,"abstract":"   Purpose of the study. To characterize copper nanoparticles obtained in reverse micelles of sodium bis-(2-ethylhexyl)-sulfosuccinate (AOT) using flavonoids: quercetin and rutin in comparison with traditional reducing agents - sodium borohydride and hydrazine.   Methods. Chemical synthesis of copper nanoparticles, spectrophotometry to determine the maximum of the plasmon absorption band of copper nanoparticles, electron transmission microscopy.   Results. The reduction of copper ions using flavonoids – quercetin and rutin – confirmed the possibility of obtaining copper nanoparticles in the Cu+2/AOT/isooctane system (AOT is sodium bis-(2-ethylhexyl)-sulfosuccinate, an anionic surfactant that forms the micelle shell). During the formation of nanoparticles, “plasmonic” absorption bands were observed in the electronic spectra in the region of 400-440 nm. In the case of the traditional reducing agent, sodium borohydride, absorption is observed in the region of (439 ± 3) nm, which can also be attributed to the “plasmonic band” of copper nanoparticles, but its intensity is very low, which indicates the formation of a small amount of copper nanoparticles. Using transmission electron microscopy. The average size of copper nanoparticles was determined: 7.1, 8.2 and 18.5 nm in the case of quercetin, rutin and hydrazine, respectively. From the histograms constructed from the results of electron transmission microscopy, it follows that the use of flavonoids as reducing agents makes it possible to reduce the average size of copper nanoparticles and narrow their size distribution.   Conclusion. Copper nanoparticles obtained in a reverse micellar solution of AOT in iso-octane using the flavonoids quercetin and rutin as a reducing agent have an average size of 7-8 nm and a narrower size distribution compared to reduction with hydrazine.","PeriodicalId":117184,"journal":{"name":"Proceedings of the Southwest State University. Series: Engineering and Technology","volume":"5 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141686134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the diffusive model of C60 fullerene clusterization in liquids","authors":"L. V. Elnikova, V. G. Shevchenko, A. P. Kuzmenko","doi":"10.21869/2223-1528-2024-14-2-156-167","DOIUrl":"https://doi.org/10.21869/2223-1528-2024-14-2-156-167","url":null,"abstract":"   Purpose of research. The purpose of the study is to explain the mechanisms of clustering of fullerene molecules in liquid media observed using various structural nuclear -physical methods, as well as the interpretation of experimental data within the framework of a microscopic diffusion model.   Methods. The article gives a brief overview of the results of positron annihilation spectroscopy, small-angle neutron scattering, translucent electron microscopy, with which the geometric parameters of fullerene clusters in solutions were established. The theoretical method of research is the microscopic diffusion model “Limited diffusion aggregation”, which describes the kinetic processes of clusterization.   Results. The diffusion limited aggregation model displays adequately the mechanism of formation of C60 molecules in the form of fractal units in the volume of fluid, observed in experiments on positron annihilation spectroscopy and small-angle neutron scattering. The structural indicators of aggregate fullerene particles in carbon disulfide, o-Xylene, toluene, water and other solvents are analyzed. The properties of various diffusion models (the reaction limited aggregation model and the diffusion limited aggregation model) are considered and their combination in relation to the assessmentsof the kinetics of fullerene aggregation in solutions. A quantitative comparison of the results of the discussed models was carried out using the example of carbon disulfide.   Conclusion. The diffusion microscopic models adequately describe the phenomenon of fullerene aggregation in polar and non-polar solvents, which are recorded by various nuclear methods (positron annihilating spectroscopy and small-angle neutron scattering), the most reliable is the diffusion limited aggregation model, more than that, it is the basis of a numerical definition of structural structures parameters of units. Compared to neutron scattering, with the annihilation of positrons, in the aggregation of fullerene the [Ps–C60] molecular complexes participate in the clusterization, but this does not affect the change in the size of the cluster and the reliability of the results.","PeriodicalId":117184,"journal":{"name":"Proceedings of the Southwest State University. Series: Engineering and Technology","volume":"23 19","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141684884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulation of ordering and diffusion in CrxMoNbTaVW alloys within the framework of the N-body approach when specifying interatomic interactions","authors":"V. N. Maksimenko, A. G. Lipnitskii, N. V. Malai, V. M. Emelyanov","doi":"10.21869/2223-1528-2024-14-2-88-107","DOIUrl":"https://doi.org/10.21869/2223-1528-2024-14-2-88-107","url":null,"abstract":"   Purpose. Development of interatomic potentials for atomistic simulation of alloys based on refractory metals of the V-Cr-Nb-Mo-Ta-W system and atomistic simulation using these ordering and diffusion potentials in CrxMoNbTaVW alloys.   Methods. The development of the interatomic potentials of the V-Cr-Nb-Mo-Ta-W system was carried out within the framework of the 𝑁-body approach; To optimize the parameters of the potentials, the results of calculations within the framework of the electron density functional theory using the VASP software package were used as target values; the simulations of ordering and diffusion was carried out using methods of molecular dynamics and the developed We have previously used the combined method of molecular dynamics and the Monte Carlo method (MD+MK).   Results. Within the framework of the 𝑁-body approach, potentials are constructed that complement the V-Nb-Mo-W potential system that we built earlier to the V-Cr-Nb-Mo-Ta-W system. The constructed potentials predict the characteristics of alloys in good agreement with experimental data, CALPHAD data and density functional theory data. Using these potentials by the MD+MC method, CrxMoNbTaVW alloys were modeled, where 𝑥 = 0, 0.5, 1, 2 and 3, in the temperature range from 500 ºC to 2300 ºC. The MD+MC calculations and CALPHAD data agreed in the temperature and concentration regions containing one phase of BCC. At a temperature of 1000ºC, MD + MC calculations show the presence of a single BCC phase, which contradicts CALPHAD data, but is consistent with experimental data. The simulation showed that the atomic structure of the CrMoNbTaVW model alloy is self-sufficient to realize the diffusion of components without artificial introduction of vacancies. The absolute values of the diffusion coefficients of the components and the values of the effective activation energy of diffusion in a solid solution of CrMoNbTaVW were calculated for the first time by the method of molecular dynamics. Analysis of the calculated diffusion characteristics indicates that a diffusion mechanism is implemented in the CrMoNbTaVW alloy, which includes coordinated movement of atoms of various grades.   Conclusion. The development of methods for atomistic simulations of alloys based on refractory metals of the V-Cr-Nb-Mo-Ta-W system and the results of atomistic simulation of ordering and diffusion in CrxMoNbTaVW alloys have shown their importance for explaining and predicting heat resistance caused by diffusion processes in multicomponent alloys at high temperatures.","PeriodicalId":117184,"journal":{"name":"Proceedings of the Southwest State University. Series: Engineering and Technology","volume":"36 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141693096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magnetron carbon structures obtained by high-frequency magnetron sputtering in Argon and Nitrogen","authors":"A. P. Kuzmenko, A. I. Kolpakov, A. S. Sizov, V. M. Emelyanov, Y. A. Neruchev","doi":"10.21869/2223-1528-2024-14-2-71-87","DOIUrl":"https://doi.org/10.21869/2223-1528-2024-14-2-71-87","url":null,"abstract":"   Purpose of research. Creation and characterization of carbon nanostructures by high-frequency magnetron sputtering from a carbon target in argon on a silicon substrate and in a reactive nitrogen environment, obtained on a Ni catalyst buffer layer.   Methods. High-frequency magnetron sputtering on a silicon substrate with changes in control parameters: sputtering time power and working gas pressure Ar and N. Research was carried out using X-ray phase analysis, atomic force microscopy and holographic microscopy, Raman scattering.   Results. The formation of carbon nanotubes, including single-walled ones, was confirmed by the method of Raman scattering of light along the lines ID 1363 and IG 1564 cm-1, as well as ωRDМ 308 and 227 cm–1. Using atomic force microscopic images, the fractal dimension of the nanofilms was calculated, which indicated their 3D nature. Based on X-ray phase analysis of magnetron nanofilms, the dimensions of the coherence region, texture, microdeformations and interplanar deformation distortions were determined.   Conclusion. In carbon magnetron nanofilms, deformations of both signs occur: both compressive (∆a < 0) and tensile (∆a > 0). Carbon magnetron nanofilms are represented, among other things, by single-walled carbon nanotubes, the chirality of which in an argon environment is (6, 6), and in a reactive mixture of nitrogen and argon on a Ni buffer layer (7, 7). It was discovered that in high-frequency magnetron mode, silicon carbide is formed in both inert and reactive environments.","PeriodicalId":117184,"journal":{"name":"Proceedings of the Southwest State University. Series: Engineering and Technology","volume":"51 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141691278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structure and properties of alloys based on electroerosive brass powder LS58-3 obtained in distilled water","authors":"E. V. Ageeva, L. S. Abolmasova, A. Pereverzev","doi":"10.21869/2223-1528-2024-14-2-45-54","DOIUrl":"https://doi.org/10.21869/2223-1528-2024-14-2-45-54","url":null,"abstract":"   The purpose of this work was to study the microstructure and physico-mechanical properties of alloy blanks based on electroerosive powder brass of the LS58-3 brand obtained in distilled water.   Methods. To carry out the planned research, waste of the LS58-3 alloy was selected. Distilled water was used as the working fluid. In an experimental patented installation for producing powders, waste LS58-3 alloy was dispersed in distilled water with a load mass of 300 g. The following modes were used: capacitor capacity 45–65 μF; voltage at the electrodes from 150–200 V; pulse repetition rate 50–100 Hz. The preparation of new alloy blanks was carried out using an SPS 25-10 electric spark plasma sintering installation (ThermalTechnology, USA). The microstructure of new alloy workpieces was studied using an electron-ion scanning (raster) microscope QUANTA 600 FEG (Netherlands). The study of the porosity of workpieces of new alloys was carried out using an optical inverted microscope OLYMPUS GX51 (Japan). The study of microhardness of workpieces of new alloys was carried out using an automated microhardness tester AFFRI DM-8 (Vickers).   Results. Analysis of the microstructure showed that the sample has a fine-grained structure and a homogeneous surface. According to the obtained porosity analysis results, the sample has less than 1% pores, which is achieved thanks to the technology of spark plasma sintering of the powder. Analysis of the microhardness of the sample showed a significant increase in microhardness, which is explained by the presence of high-hard particles formed during quenching of metal vapor in the working fluid during dispersion.   Conclusion. The use of spark plasma sintering technology for electroerosive brass makes it possible to obtain blanks of new alloys with a practically non-porous structure, which leads to an increase in the hardness of the resulting blanks. The results of the conducted studies make it possible to recommend the use of the resulting powder as a starting material for the production of alloy blanks and to expand the scope of their practical application.","PeriodicalId":117184,"journal":{"name":"Proceedings of the Southwest State University. Series: Engineering and Technology","volume":"23 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141706191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of external magnetic field on the viscosity of electrically conducting magnetic fluids","authors":"K. Komilov, A. Q. Zarifzoda","doi":"10.21869/2223-1528-2024-14-2-55-70","DOIUrl":"https://doi.org/10.21869/2223-1528-2024-14-2-55-70","url":null,"abstract":"   Purpose. Theoretical study of an external magnetic field on the discontinuous and bulk viscosity of electrically conductive magnetic fluids.   Methods. The method of molecular kinetic theory is used, which, using kinetic methods for single-particle and two-particle distribution functions, allows one to determine transfer mechanisms in electrically conductive magnetic fluids.When constructing kinetic mathematical electrically conductive magnetic fluids as multicomponent systems in which non-magnetic and magnetic subsystems are independent, magnetic particles and the stabilizer substance closely interact with each other.   Results. Based on algorithms of expressions for the coefficients of shear and volumetric viscosity, the observed mechanisms of translational and structural relaxation processes, a series of calculations was carried out depending on thecoefficients of stepwise and volumetric viscosity from the results of external magnetic fields, the volumetric structure of magnetic particles and the calculation of measured values in electrically conductive magnetic fluids based on mercury and a eutectic alloy of Gallium and India. It is shown that with increasing external magnetic fields, the coefficients of shear and bulk viscosity in electrically conductive magnetic fluids increase nonlinearly. An increase in the volume of elements of magnetic particles also leads to a nonlinear increase in the coefficients of abrupt and bulk viscosity.   Conclusion. The given calculations of the coefficients of shear and bulk viscosity depending on the principle of international dependence indicate that the use of metal constants in electrically conductive magnetic fluids leads to a noticeable decrease in their viscosity. It is shown that the results obtained, in good agreement with literature data, can be used for further development of the theory of transfer processes of electrically conductive magnetic fluids.","PeriodicalId":117184,"journal":{"name":"Proceedings of the Southwest State University. Series: Engineering and Technology","volume":"7 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141698399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis of Eu-doped TiO2 nanoparticles by hydrothermal method","authors":"I. V. Egelskii, M. A. Pugachevskii, E. A. Martynova, Y. A. Neruchev","doi":"10.21869/2223-1528-2024-14-2-108-121","DOIUrl":"https://doi.org/10.21869/2223-1528-2024-14-2-108-121","url":null,"abstract":"   Purpose of research. Synthesis, characterization and comparison of the photocatalytic properties of europium-doped titanium dioxide nanoparticles.   Methods. Europium-doped titanium dioxide nanoparticles were synthesized via a hydrothermal method followed by post-treatment processes including washing and annealing. Characterization was conducted using transmission electron microscopy, X-ray phase analysis, and energy-dispersive analysis. The bandgap width of the nanoparticles was determined through diffuse reflectance spectroscopy. Photoluminescence properties were studied using scanning probe microscopy and Raman spectroscopy. The photocatalytic properties were studied by spectrophotometry to determine the degradation of methylene blue under ultraviolet radiation.   Results. Transmission electron microscopy identified the average particle sizes of europium-doped titanium dioxide. Using X-ray phase analysis, it was established that the nanoparticles were in the anatase phase regardless of the europium content percentage. Energy-dispersive spectroscopy confirmed the presence of the dopant in the samples. The photoluminescence intensity peak increased proportionally with the increase in europium content percentage. The strongest photocatalytic properties were exhibited at the lowest europium content among the samples studied.   Conclusion. Synthesized and processed europium-doped titanium dioxide nanoparticles with anatase polymorphic modification exhibit photoluminescent properties. The luminescence intensity depends on the concentration of europium in the particles, due to the formation of additional energy levels inside the band gap. The photocatalytic properties of europium-doped nanoparticles are significantly improved in comparison with samples synthesized without impurities. However, a europium concentration above 0,5% leads to the growth of structural defects that reduce the mobility of photogenerated charge carriers and creates a high energy barrier that prevents them from reaching the surface.","PeriodicalId":117184,"journal":{"name":"Proceedings of the Southwest State University. Series: Engineering and Technology","volume":"272 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141712317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the effectiveness of using carbamide-based salt baths for low-temperature cyanidation of improved carbon and alloy steels","authors":"N. N. Kostin, V. I. Kolmykov, N. A. Kostin, D. V. Kolmykov","doi":"10.21869/2223-1528-2024-14-2-33-44","DOIUrl":"https://doi.org/10.21869/2223-1528-2024-14-2-33-44","url":null,"abstract":"   Purpose. A study of cyanidation of improved carbon and alloy steels of grades 30, 30HGT, 30H13 at a temperature of 550–580 °C was carried out in baths based on carbamide and sodium carbonate. Recommendations on the use of these baths for surface hardening of carbon and alloyed improved steels used for the manufacture of machine parts are formulated.   Methods. The microstructure of the diffusion layer of steels on transverse sections was studied using a Quanta FEG – 650 electron scanning microscope with an EBCD focused ion beam microanalysis system. Cyanide wear tests were performed under friction conditions analogous to those of die tools. The wear resistance of the carbonitrided samples was investigated on a SMTs-2 friction machine. The tests were performed under both dry friction and boundary friction conditions.   Results. The high efficiency of the proposed bath composition at a given temperature has been experimentally shown. As a result of cyanidation, modified layers saturated with solid inclusions (ε-phases) are formed on the surface of steels, characterized by high hardness, low coefficient of friction and high wear resistance.   Conclusion. According to the results of the conducted research, it can be concluded that low-temperature cyanidation of improved steels of various grades can be carried out in cyanide-free salt baths. The optimal composition of the cyanide bath is 40% carbamide (NH2)2CO; 40 % soda ash Na2CO3 and 20 % NaCl table salt. The proposed bath does not contain toxic and scarce components, therefore it is environmentally safe and very cheap and can be used with great effect in machine-building, repair and tool industries.","PeriodicalId":117184,"journal":{"name":"Proceedings of the Southwest State University. Series: Engineering and Technology","volume":"133 34","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141714334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}