Diffusion Saturation Research Articles

Framework for electrochemical-mechanical behavior of all-solid-state batteries: From the reconstruction method to multi-physics and multi-scale modeling

All-solid-state batteries (ASSBs) are high-energy, high-power batteries. To enhance the understanding of the electrochemical-mechanical behavior in ASSBs across different scales, we developed a multi-physics and multi-scale modeling framework. This framework incorporates elastoplastic finite deformation and electrode microstructures of ASSBs, and the role of gradient plasticity in the governing equation for multiple physical fields was discussed. Utilizing X-ray computed tomography, we reconstructed the microstructure through a machine learning (ML)-informed image segmentation process. Our study clarifies the impact of electrode microstructures on concentration, stress, voltage, delamination and buckling from AM to electrode scale. Comparative analysis of the Feret diameter distribution of active materials (AMs) shows that ML-informed image segmentation outperforms two traditional segmentation methods. We observed that the asynchronous diffusion saturation of AMs, varying in shape and size, significantly influences the electrochemical-mechanical behavior of ASSBs, resulting in complicated debonding indices and J-integral distribution at the interface. The proposed upscaling homogenization procedure is demonstrated to be efficient for buckling analysis, with the shape mode closely matching existing experimental observations. These results shed light on the critical multi-physics and multi-scale coupling mechanisms in ASSBs.

Influence of electrophysical characteristics of plasma electrolytic treatment of 16MnCr5 structural alloy steel on structural and phase changes in the surface and its tribological properties

The possibility of using plasma electrolytic technologies for surface treatment of 16MnCr5 steel in order to increase its wear resistance is shown. The influence of electrophysical characteristics of plasma electrolytic treatment on structural-phase changes of the surface and its tribological properties is studied. A comparison of anodic and cathodic variants of diffusion saturation, as well as subsequent polishing on the results of surface modification is carried out. The complex effect of surface layers strengthened above 1100 HV, including iron carbide and nitride, martensite and retained austenite, to a depth of up to 250 μm with the preservation of a viscous core and the formation of a relatively homogeneous surface with reduced roughness on increasing wear resistance has been revealed. The features of tribological behavior of surfaces formed under different electrophysical parameters of processing, mainly related to the difference in surface microrelief, are shown. The correlation of the Kragelsky-Kambolov criterion as a complex assessment of surface roughness with its wear resistance is shown. The influence of changes in sliding speed and friction load on the occurrence and development of leading processes that determine the intensity and nature of destruction of friction surfaces is established.

FORMATION OF TWO-PHASE ZONES DURING INTERNAL OXIDATION OF BINARY ALLOYS

In the paper the formation patterns of two-phase regions during the internal oxidation process in low-alloyed binary alloys is studied. The goal of the research is the creation of a mathematical model for the internal oxidation process, which is to describe the kinetics of formation and evolution of internal oxidation zones, the study of the patterns governing the two-phase zone formation during internal oxidation, the study of the space-time dynamics of the structural parameters of the two-phase area, namely the number of the oxide particles, their average radius and the phase volume, at different stages of the internal oxidation zone evolution. The two-phase process of diffusion saturation with light components applied to binary alloys is analyzed theoretically. The conditions for formation of disperse oxide particles are formulated. A mathematical model for the formation of two-phase areas as well as the numerical solution for the system of equations describing the kinet- ics of formation and evolution of the two-phase area for different values of the process parameters is proposed. The modeling and experiments demonstrate that the distribution of structural parameters of the two-phase area has complex, non-monotonous nature. The influence of the main parameters of the process on the kinetics of the formation of the two-phase area in a lightly-alloyed binary nickel-based alloy plate is also determined. All stages of the plate’s oxidation process are studied – from the inception of the particles to the coalescence of second-stage particles. The results of the work could be used for developing new technologies in thermal and chemical-thermal treatments for disperse strengthening of materials using internal oxidation, as a physical basis for seeking ways of providing certain distributions of the internal oxidation zone structural parameters, which are required to give the al- loy a necessary set of physical and mechanical properties. The comparison of the modeling and experimental results shows a good correlation, which allows them to be recommended for developing new technologies in disperse strengthening, new heat-resistant steels, disperse-strengthened magnetic materials and electrotechnical alloys.

Research of the vacuum thermocyclic nitrogen process in a plasma pulsing glow discharge

As a result of the studies, the regularities of the influence of vacuum thermocyclic nitriding in a pulsating glow discharge plasma parameters on the microhardness, the diffusion saturation depth, the magnitude and distribution of residual stresses in the hardened layers of steel surfaces are established. Based on the use of expert assessment methods and the results of a series of screening experiments, optimization criteria (endurance limit and corrosion resistance) and controlled factors for mathematical modeling of the formation of strengthened ion-nitrated surface layers are determined. A mathematical model of the technology of the formation of reinforced surfaces of the vacuum thermocyclic nitriding in a pulsating glow discharge plasma according to the criteria of endurance and corrosion resistance is obtained. An analysis of the studies showed that there are no general conclusions and recommendations on the selection of optimal technological parameters of the vacuum thermocyclic nitriding in a pulsating glow discharge plasma that would be used for the practical application of this technology. These circumstances confirm the need for further study of the vacuum thermocyclic nitriding in a plasma of a pulsating glow discharge of vacuum thermocyclic nitriding in a pulsating glow discharge plasma technology and the feasibility of its optimization.

Diffusion-reaction models for concrete exposed to chloride-sulfate attack based on porosity and water saturation

Reinforced concrete structures in an unsaturated state experiences significant degradation when exposed to combined chloride and sulfate attack in marine environments. For evaluating durability and predicting service life of reinforced structures, it is crucial to better understand ions diffusion, porosity variation and water saturation of concrete. Considering effect of porosity and water saturation degree on chloride diffusivity, a new diffusion-reaction model was established to investigate how concrete degrades exposed to the severe marine environment. The model was validated using experimental results from both hydrophobic and plain concrete that had undergone a 14-month exposure test at the Qingdao Wheat Island exposure station. The simulation results of the multi-ions model showed that both plain concrete and hydrophobic concrete experienced maximum reduction of chloride concentration of about 68% when compared to concrete exposed to the unsaturated condition.

A statistical method for determining the mode of ion-plasma nitriding

Mathematical planning is used in order to determine the optimal mode for ion nitriding of the 38Cr2Ni2Mo structural steel. This is justified by the requirement to preserve strictly limited functional parameters obtained as a result of diffusion saturation: hardness ranging between 450 and 650 HV in a 0.15–0.40-mm-deep layer. The implementation of factor planning and the regression processing of the obtained data enable us to arrive at an analytical expression in the form of a linear function for the studied optimization parameters (microhardness and layer depth). This makes it possible to assess the degree and direction of the influence of the factors under study on the optimization parameters of interest.

Current invariant as fundamental relation between saturation currents and band gaps for semiconductor solar cells

The optimization of present multijunction junction solar cells and the development of new concepts is an important task for modem photovoltaics. For its development, special attention should be paid to the potential quality of photoactive p-n junctions, as well as to their properties when operating at various temperatures. The present research has shown that for two-diode model of the p-n junction it is convenient to use current invariants Jz1 and Jz2 for calculating the diffusion and recombination saturation dark currents J01 and J02 for p-n junctions based on semiconductor materials with any band-gap energy. It has been experimentally found that Jz1 and Jz2 are constants relating the semiconductor material band gap energy and temperature with J01 and J02. It has also been shown that Jz1 and Jz2 determine the open circuit voltage and the value of voltage offset WOC. Current invariant suggested to be useful tool for evaluating the quality of a p-n junction and for modeling the characteristics of solar cells because it allows making calculations taking into account both main mechanisms of current flow and the operating temperature of the device.

Comparative Analysis of Diffusion Metallization Coatings Applied on Steel Parts

In this paper the positive and negative aspects of diffusion metallization of steels were reviewed. It was shown that at high heating temperatures and prolonged exposure under these temperatures, steels show a tendency to enlarge austenitic grain. Overheating can occur at high exposure temperatures (T>1000ᵒC), which can be rectified by repeated heating however if burning of the steel microstructure occurs, it cannot be corrected. Given these circumstances, when assigning diffusion metallization modes, it is necessary to consider the factor of overheating or burning of steel in the process of exposure to high temperatures. To avoid this phenomenon, it is recommended to use alternative low-temperature processes of diffusion saturation of steels. Nitriding, nitro-cementation, gas-thermal spraying of the surface of steels are shown as such examples. It was suggested that these processes in comparison with diffusion metallization are more promising and acceptable for the restoration of worn surfaces of steels in the manufacture of parts of specialized equipment. Given that the parts of specialized equipment work in extreme conditions, repeated high-temperature heating of these steels is not recommended.To overcome the shortcomings of the diffusion metallization, the most frequently used coatings are applied by CVD, thermal spray, and cloth cladding techniques. As an alternative promising solution, the development of innovative methods of diffusion saturation, like an ion plantation of atoms on a relatively cold surface of the part could also be considered. It is shown that diffusion metallization is most acceptable for saturation of the surface of non-ferrous metals and alloys with the hardest and wear-resistant compounds.

Phase Composition and Biocompatibility of Coatings Produced on Ti–6Al–5V Titanium Alloy via Diffusion Saturation with Oxygen, Nitrogen, and Carbon

Phase Composition and Biocompatibility of Coatings Produced on Ti–6Al–5V Titanium Alloy via Diffusion Saturation with Oxygen, Nitrogen, and Carbon

Research of Increase of the Wear Resistance of Machine Parts and Tools by Surface Alloying

The work scientifically substantiates the application of an effective technology for increasing the wear resistance of machine parts and tools due to complex diffusion saturation of the surface layer of parts made of iron-carbon alloys in the process of casting on gasified models based on the optimization of the composition of saturating mixtures and the establishment of patterns of structure formation.
 The possibility of strengthening the surface of castings from cast iron SCH20 and steels of various composition (25L, 30L, 35L, 45L, 25HL, 110H13L), obtained by methods of casting in an open mold and on gasified models, has been established. It is shown that the diffusion boride layer on 35L steel, obtained during casting, has an order of magnitude greater thickness (up to 5 mm) compared to the diffusion layers obtained by chemical-thermal treatment methods (up to 0.25 mm). Analytical dependencies have been established that connect the components of the composition of the mixture (chromium boride (CrB2), boron carbide (B4C), graphite, bentonite, sodium fluoride (NaF)), which saturates, with wear resistance and the thickness of the diffusion layer after hardening in the process of obtaining a casting by the method of casting on gasified models.
 A new composition of the saturating medium has been developed for surface strengthening in the production of cast parts from gray iron, carbon and alloy steels by simultaneous saturation with boron and chromium, containing chromium boride, boron carbide, graphite, bentonite, sodium fluoride (50-60 wt. % B4C + 20-25 wt. % CrB2 + 2-3 wt. % + 5-15 wt. % finely dispersed graphite + 5-7 wt. % bentonite). The application of the developed strengthening technology allows to improve operational properties, in particular, the wear resistance of machine parts and tools up to 25 times (compared to previously used methods), as well as to reduce the labor intensity of the strengthening process by up to 3.5 times.
 Tests of dies for pressing wood waste into briquettes made of 45L steel, strengthened with the help of the developed technology, showed that their stability increases more than 4.5 times compared to the previously used ones made of HVH steel strengthened by carbonitriding, and the use of the developed strengthening technology allows reduce the cost of manufacturing this part by 1.5 times.

The Feasibility of Dose-Escalated Radiation Therapy for Glioblastoma Using Biological Image Guided Adaptive Radiotherapy (BIGART)

Radiotherapy dose escalation (DE) for glioblastoma (GBM) has been an area of active research. We aimed to study the imaging changes within residual gross tumor volumes (GTV) through the course of concurrent chemo-radiotherapy (CCRT) using multiparametric magnetic resonance imaging (mpMRI). Diffusion, perfusion and chemical exchange saturation transfer (CEST) characteristics of the tumor and its microenvironment were investigated to identify a GTV subvolume potentially associated with radio resistance. We used biological image-guided adaptive radiotherapy (BIGART) to study the feasibility of DE to this GTV subvolume using either photon or proton beam therapy (PBT). We prospectively identified GBM patients with >5cc residual tumor post-resection who were candidates for radical CCRT (60 Gy in 30 daily fractions over 6-weeks with concurrent temozolomide 75mg/m2 daily). We observed the imaging changes with serial mpMRI scans done at baseline, after 2, 4 and 6-weeks of CCRT. Regions of interest (ROIs) within the GTV associated with the following abnormal values at week 2 were identified: apparent diffusion coefficient (ADC): 750-1000 ×10-6 mm2/s; relative cerebral blood volume (rCBV): 1.75-6; and APT-w CEST signal intensity >1.79%. The overlap regions of these ROIs were defined as a novel biological target volume (BTV), identifying the potential area of maximal radioresistance. An in silico study was performed using a technology company's treatment planning system to evaluate the feasibility of planning adaptive treatment to the BTV to total dose of 75 Gy in 30 fractions. This is given in two phases: 30 Gy/15# to the whole PTV as per standard practice, followed by a simultaneous integrated boost (SIB) of 45 Gy/15 fractions while maintaining the dose to the rest of the of the PTV to 60 Gy. Either photons or PBT were used to keep doses to organs at risk (OARs) within standard clinical tolerances. Nine patients were recruited for this analysis and a total of 27 mpMRI scans were studied. Median BTVs to GTVs ratio was 35% (range 22-47%). Volumetric-modulated arc (VMAT) photon and PBT adaptive plans for dose escalation to BTVs were created in all cases whilst maintaining OAR tolerances. Both VMAT and PBT provided acceptable target coverage with average BTV-PTV D98% of 73 Gy (range 71.5-73.8 Gy) and average D2% of 76 Gy (range 75.4-77 Gy) while effectively sparing OARs. Sharper dose gradient between DE-BTV and PTV was achieved with VMAT. PBT was particularly advantageous in minimizing the low-dose spillage outside the BTV. We hereby propose a platform for adaptive radiotherapy to GBM tumors with biological-image guidance through the utilization of mpMRI to evaluate the tumor and its microenvironment during CCRT. We identified thresholds for tumor sub volumes showing the most resistant imaging features and created precise BTVs that allowed for dose escalation. PBT represents an additional useful tool for BIGART planning that will be investigated further in our ongoing work.

(Invited) Coupled Quantum Emitters in Carbon Nanotubes

The development of covalent diazonium functionalization of carbon nanotubes brings unique opportunities in terms of original quantum sources of light. In particular, it should be possible to create a linear ensemble of closely packed single-photon sources along the carbon nanotube backbone. The physical proximity of several dopants would make it possible to couple them simultaneous to a resonant cavity mode and to induce original dynamics and light emission properties. Here, we investigate experimentally the case of a series of four quantum emitters attached to the same carbon nanotube coupled to a high finesse fiber cavity. We explore their properties through PLE, polarization and super-localization measurements and their light emission properties using time-correlation techniques and photo-luminescence decay measurements. We show that two pairs show qualitatively different behaviors in terms of spectral diffusion and luminescence saturation, which we interpret using two models of electronically coupled or uncoupled two-level systems.

Experimental study on chloride ion diffusion behavior and microstructure in concrete under alternating ambient humidity conditions

The migration of chloride in concrete in atmospheric zones is mainly influenced by climatic conditions, e.g., various dry-wet cycles in marine tidal zones, and ambient humidity is one of the most important influences. Ambient humidity also determines the moisture content in concrete, which is necessary for the diffusion or transport of chloride in concrete and can enhance the migration of chloride in micropores, thus affecting the distribution of chloride in concrete. In this study, the effects of chloride diffusion and its mechanism, and the evolution of moisture in concrete under alternating drying-wetting cycles, were investigated using an environmental moisture simulation chamber. Chloride diffusion tests were also performed to evaluate the effects of different dry-wet ratios and numbers of drying-wetting cycles on the chloride diffusion depth, chloride content and saturation in concrete. The microstructure of concrete was studied and analyzed using XRD, SEM and MIP technology. The findings showed that the saturation of concrete decreased rapidly with increasing number of wet-dry cycles and finally stabilized. Under different alternating moisture conditions, the saturation of concrete was greater, especially when the wetting time was longer. Additionally, in areas near the surface of concrete (depths of 2 mm-6 mm), the chloride content was proportional to the number of wet-dry cycles. In the interior of concrete (depth > 6 mm), when the number of drying-wetting cycles was larger, the chloride concentration was smaller. However, as the number of wet-dry cycles increased, this led to the decalcification of C-S-H gels, which resulted in the reduction in the number of C-S-H reticular gels with good crystallinity. A pore analysis showed that the cumulative pore size and the maximum probability pore size of concrete gradually increased with increasing number of wet-dry cycles, the deterioration of pore structure was more obvious, and the compactness of concrete gradually decreased, which accelerated the migration of chloride in the matrix. Overall, this study can provide reliable and valuable test data for the development and design of high-performance concrete for applications in atmospheric marine tidal zones.

Possibilities of Duplex Plasma Electrolytic Treatment for Increasing the Hardness and Wear Resistance of a Commercially Pure Titanium Surface

The technology for duplex treatment of a commercially pure titanium surface is expected to increase hardness and wear resistance. This technology consists of sequential nitrocarburizing and polishing of the product in plasma electrolysis. The mechanism of duplex processing is revealed; it consists of strengthening the surface layers under diffusion saturation and controlled formation of the surface relief. The possibility of controlling the characteristics of the modified surface by combining various plasma technologies is shown. The morphological features of the surface and the surface layer after treatment were studied. The microhardness of the modified layer and the tribological properties of the surface were measured. It has been established that the samples with the highest surface layer hardness and a small thickness of the oxide layer on the surface have the highest wear resistance. After nitrocarburizing at 750 °C for 5 min, wear resistance increases by 4.3 times compared to pure material. If subsequent polishing is carried out at a voltage of 275–300 V for 3–5 min in chloride and fluoride electrolytes and 5–10 min in a sulfate electrolyte, then wear resistance can be further increased. This is achieved by removing the porous outer oxide layer.

Управление эксплуатационными свойствами порошковых материалов для повышения коррозионной стойкости и износостойкости деталей

Introduction. One of the vibration methods for processing loose finely dispersed mineral raw materials is the sepIntroduction. The quality of powder materials made of rare metals is ensured by chemical-thermal treatment, including diffusion chromosilidation. Chemical and thermal treatment of products intensifies the process of diffusion saturation, reduces the processing time and allows the use of products in aggressive and abrasive environments. Methods and materials of research. Systematization, generalization and analysis of theoretical, laboratory and experimental studies, the basis of which is the modeling of processes. Research results. It was found that when using low-alloyed powder, higher strength and viscosity indices of chromosilicated materials were obtained. It is determined that the mechanical properties of powders processed from molten salts are higher than those of materials from powder filling. It is shown that the treatment increases the corrosion resistance of iron-based powders with an established corrosion rate less than the initial one. Discussion of research results. The rapid formation of an oxide film that protects the metal from corrosion is facilitated by quenching and normalization. Porous chromosilicated layers are destroyed and impair the ability of the material to resist corrosion destruction. The operational properties of chromosilicated powders obtained by hot stamping methods increase when using rational parameters of the technological process in an optimal mode. Conclusion. The article contains new proposals for managing the properties of materials to increase corrosion resistance and wear resistance of children. Conclusions on the article. New developments can be recommended for implementation in the production of rare metals and products made from them. Suggestions. The results of the research can be used both in the modernization of production and in the training of specialists in this field.

Oxygen diffusion saturation of hafnium with the different surface layer

Hafnium is used for the production of control rods and protective screens in nuclear reactors after its hot plastic deformation and final thermochemical treatment. This research presents the experimental results of the influence of the surface layer state on the oxygen diffusion saturation of hafnium during thermochemical treatment in an oxygen-containing gas medium. Two cases of the surface layer state were considered: in the initial (delivery) state and after grinding, where 50 μm of the surface layer was removed. Differences between the hardness distributions in the near-surface layer of HFE-1 hafnium after thermochemical treatment in an oxygen-containing gas medium were shown. It was found that thermochemical treatment of hafnium with a surface layer in its initial state leads to an increase of hardness in the near-surface layer compared to the surface: i.e., the near-surface layer hardness increases to a depth of 5 - 7 μm, and then gradually decreases to the matrix (core) hardness. It was determined that the fatigue life of hafnium after thermochemical treatment depends on the surface layer state. A 6.5 times higher fatigue life after thermochemical treatment of hafnium samples was fixed with a grinded surface compared to hafnium samples without grinding.

Deterministic random walk model in NetLogo and the identification of asymmetric saturation time in random graph

Interactive programming environments are powerful tools for promoting innovative network thinking, teaching science of complexity, and exploring emergent phenomena. This paper reports on our recent development of the deterministic random walk model in NetLogo, a leading platform for computational thinking, eco-system thinking, and multi-agent cross-platform programming environment. The deterministic random walk is foundational to modeling dynamical processes on complex networks. Inspired by the temporal visualizations offered in NetLogo, we investigated the relationship between network topology and diffusion saturation time for the deterministic random walk model. Our analysis uncovers that in Erdős–Rényi graphs, the saturation time exhibits an asymmetric pattern with a considerable probability of occurrence. This behavior occurs when the hubs, defined as nodes with relatively higher number of connections, emerge in Erdős–Rényi graphs. Yet, our analysis yields that the hubs in Barabási–Albert model stabilize the the convergence time of the deterministic random walk model. These findings strongly suggest that depending on the dynamical process running on complex networks, complementing characteristics other than the degree need to be taken into account for considering a node as a hub. We have made our development open-source, available to the public at no cost at https://github.com/bravandi/NetLogo-Dynamical-Processes.

Application of Diffusive Saturation with Boron Together with Aluminum for Hardening of Die Tooling Made of 5KhNM Steel

Application of Diffusive Saturation with Boron Together with Aluminum for Hardening of Die Tooling Made of 5KhNM Steel

The application of cumulating lattice to accelerate diffusion during thermal diffusion chromiing

The creation of coatings on parts with improved corrosion resistance, throughput at low and high temperatures, wear resistance makes it possible to expand the possibilities of using low and medium alloy steels. Traditional methods for creating protective coatings are various types of chemical-thermal treatment and thermal diffusion chromium plating, in particular. In recent decades, attempts have been repeatedly made to increase the efficiency of the process of thermal diffusion saturation of chromium metal, mainly due to complex saturation with vanadium, boron and other elements, as well as the use of external physical influences that accelerate diffusion. Previously, in the works of the authors, it was shown that the introduction of electron-emitter metal powder into the composition of the metal part of the filling ensures the acceleration of diffusion processes during thermal diffusion chromium plating due to the action of an internal emission field. A similar effect is also observed when replacing corundum in the separating part of the filling with powders of solid electrolytes (minerals such as serpentine and scheelite, which are emitters of electrons and anions of the oxygen when heated). An additional enhancement of the internal emission field was noted when cumula-tive nickel and molybdenum lattice were used, however, the effect of the geometric characteristics of these lattice on the magnitude of the thermal emission of electrons and oxygen anions and, as a result, the diffusion acceleration was not established. The paper presents the results of saturation of samples of steel X35CrNi2-3 at a temperature of 1000°C for 24 hours using cumulative lattice that differ in the density of holes per unit area: 20, 10 and 6 holes/cm2. The control of the elemental composition of the diffusion layer was carried out on transverse sections in the direction from the saturated surface to base metal of the sample using a JEOL JSM-6460LV universal scanning (scanning) electron microscope. X-ray phase analysis was performed on an Ultima IV diffractometer, the radiation used was Cu-Kα. The microstructure was studied using an optical microscope Axio Observer D1.m. The microhardness of the coatings was measured using an FM-800 microhardness tester. It has been established that the use of cumulative nickel lattices provides an increase in the depth of the diffusion layer in the base metal by at least 25% and additional alloying coating with a grating metal element with a hole density of 10 pieces/cm2 or more. At a lower density of perforating the lattice, the opposite effect is observed

Особенности формирования диффузионных покрытий, полученных комплексной химико-термической обработкой конструкционных сталей

Introduction. The main methods of increasing the efficiency of products made from structural steels are considered. A description of diffusion saturation from liquid metal media solutions (DSLMMS) is given. Also, complex diffusion saturation technology (CDS), including DSLMMS and carburization is shown. The purpose of the work is to reveal the effect of steel composition on the process of formation and elemental composition of diffusion-saturated surface layers (coatings) based on chromium, as well as to establish differences and regularities in the processes of formation of diffusion-saturated coatings after DSLMMS and CDS. The methods of investigation. Cylindrical specimens 20 mm in diameter and 30 mm long were subjected to DSLMMS. The specimens were made of carbon and alloyed steels: St3, 20-Cr13, 40-Cr, 40-Cr13, 12-Cr18-Ni10-Ti. At the same time, some of the specimens were previously subjected to vacuum cementation. An eutectic Pb-Bi with the specified content of Cr was used as a transport medium when executing DSLMMS. Metallographic studies were carried out on microsection prepared according to the standard method. Studies to determine the thickness of coatings and its structure were carried out on the Dura Scan Falcon 500 Microhardness Tester. The elemental composition of the coatings was determined by the method of electron microprobe analysis on a Tescan Lyra 3 scanning electron microscope with the Oxford Ultim MAX PCMA system. Results and discussion. As a result of the research, it was revealed that the formation of saturated coatings occurs with DSLMMS and CDS. At the same time, the thickness of the coatings and its elemental composition depend on the steel grade and the technology used. After DSLMMS concentration of Cr varies from 96.9% to 91.1%. At the same time, the maximum concentration of 96.9% is observed on steel St3. After CDS, on the surfaces of all steel samples, the concentration of Cr decreases in comparison with the coatings obtained by the DSLMMS technology on steels: St3 from 96.9% to 66.8%; 40-Cr from 91.1% to 63.18%; 20-Cr13 from 93.18% to 62.54%; 12-Cr18-Ni10-Ti from 92.92% to 64.77%. The total thickness of diffusion-saturated coatings formed on all the alloys studied ranges from 17 to 17.5 µm.