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The paper discusses the results of studying the structure and properties of powder coatings based on Ti3SiC2/TiC, obtained by the method of detonation spraying on the surface of the tool steel N9. It is determined that the coating has a uniform structure, cracks and delaminations are not observed. The results of X-ray structural analysis of coatings showed that the coating before annealing consists of phases TiC and Ti3SiC2. After annealing, the formation of TiO2 phases and an increase in the intensity of the (103) and (108) reflections of the Ti3SiC2 phases are observed. It is established that an increase in the content of the phases of Ti3SiC2 in coatings leads to an increase in the microhardness of coatings.

This work presents the experimental results of the study of the effect of heat treatment on the structural-phase state of TiN coatings on the surface of 67KH5B alloy. It is determined that thermal annealing leads to structural phase transformations at the interface between the coating and the substrate. It was established that after annealing at Т=800 °С, due to the redistribution of the coating elements and the substrate, a modified coating is formed consisting of the TiN, Ti2N and NiTi phases.

Как известно ранее, карбиды, силициды и карбосилициды металлов обладают уникальным сочетанием высокой твердости, коррозионной стойкости и износостойкости [1]. Однако получение таких фаз традиционными методами связано с высокой температурой и продолжительностью их синтеза. В то же время технология получения защитных покрытий из таких композиций ограничена. Газотермические методы (электрическая дуга, газовое пламя, плазма, детонация и т. Д.) Являются одними из наиболее широко используемых [2–5]. Во всех газотермических методах при нанесении материалов покрытия на подложку используются высокотемпературные газовые потоки, в которых частицы материала нагреваются и приобретают высокую скорость. Образование покрытия происходит, когда эти частицы взаимодействуют с подлежащим покрытию субстратом. Важным преимуществом газотермических методов покрытия является то, что они позволяют наносить различные материалы покрытия (металлы и их сплавы, оксиды, бориды, карбиды и т. Д.). Анализ классических газотермических методов нанесения покрытий показывает, что наиболее высокие прочностные свойства обеспечивают детонационные покрытия [6]

Electron microscopy and x-ray analysis and mechanical testing have been investigated the influence of severe plastic deformation on structure and mechanical properties of aluminum alloys. It is established that in the initial state in the alloy AMC has a high density of chaotically distributed dislocations with a density of 5-10*109 сm-2. It is shown that microdiffraction paintings in alloy AMC in the bulk of grains are observed uniformly distributed particles of the second phase. It is established that in the initial state in the alloy AMG6 there is a high density of chaotically distributed dislocations with a density of 2-6 *1010 сm-2. Determined that after ECAP the dislocation structure of alloys AMG6, AMC and changes: formed dislocation networks inside the fragments of the dislocation is practically not observed. Determined that after ECAP-12 increase the tensile strength and yield strength of alloys AMG6 and AMC.

Changes in the structure and the tungsten surface erosion by hydrogen plasma irradiation are studied in the article. It is shown that the change in the surface topography as a result of the development of the non-homogeneous surface etching is observed after surface irradiation. Metallographic analysis showed that the degree of relief is low in comparison with tungsten sample irradiated at T=700°C by tungsten samples irradiation at T=1000°C and 1500°C. However, these samples have small cracks, while the temperature increases the size and number of cracks also increases. It is determined, that the surface roughness varies depending on the irradiation temperature after hydrogen plasma exposure. The greatest increase in the roughness occurs in samples irradiated at T=1500°C, which is associated with the formation of small cracks in the surface layer. It is shown that a degree of surface erosion is increased with increase of the target temperature and the ion energy. Appreciable tungsten erosion due to irradiation of the plasma flow, plasma simulating stationary mode occurs only at relatively high temperatures of the target.

The article investigates the changing in the structure and phase composition of the R6M5 high-speed steel surface layer after electrolytic-plasma nitriding. It is found that after electrolytic-plasma nitriding on the R6M5 steel surface, modified layer is formed, which consist from a diffusion layer. It was showed phase composition of difysion layer is changing depending on the nitriding. It is found that electrolytic-plasma nitriding lead to accelerated formation of the modified layer. It is determined that after electrolytic-plasma nitriding on the high-speed steel surface, modified layer is formed, consisting only of the diffusion layer.

In the article the formation peculiarities of the modified layer at R9, R6M5 R18 high-speed steels (HSS) after electrolytic-plasma nitriding are shown. It is established that in the result of electrolytic-plasma nitriding on the of high-speed steels samples surfaces formed modified layers with higher hardness. Hardness of HSS increased to 11.9-12.8 HPa after electrolytic-plasma nitriding, mainly depends to the formation of a diffusion layer of nitrogen martensite with Fe4N (γ’-phase) monophasic nitride. It is determined that a modified layer consists of nitrogenous martensite with Fe4N monophasic nitride. Perspectivity of use an electrolytic-plasma nitriding method to improve performance cutting tools made of high speed steels is shown.

In the article changes in the structure and mechanical properties of R6M5 steel surface layer after electrolytic-plasma nitriding are shown. The optimal mode of electrolytic-plasma nitriding of R6M5 high-speed steel in electrolyte based on carbamide, which allows saturation of the surface with nitrogen from low-temperature plasma and get the modified layer of high hardness and wear-resistance. It is established, that after electrolytic-plasma nitriding reduced R6M5 steel wear rate and increases its resistance to abrasive wear. Perspectivity of use an electrolytic-plasma nitriding method to improve performance cutting tools made from R6M5 steel is shown.

The article examines regularities of high-speed steel surface changes in the phase and structural states of during the electrolytic-plasma processing. It is determined that after modification by electrolytic-plasma influence on the surface of R6M5 high-speed steel formation of small pores, microdefects and fine inclusion. Surface modified layer consists of nitrogen austenite, nitrogen martensite and fine nitride particles.

In this work the influence of electrolytic-plasma nitriding on the abrasive wear-resistance of R6M5 high-speed steel were under research. We registered that after electrolytic-plasma nitriding on R6M5 steel surface modified layer is formed with 20-40 μm thickness and with increased microhardness of 9000-12200 MPa. Testing mode for the nitrided samples high-speed steel on abrasive wear developed. It is established, that electrolyte-plasma nitriding allows to increase wear-resistance of R6M5 steel surface layer comparing to original. It was determined that abrasive wear-resistance of R6M5 steel surface layer is increased to 25% as a result of electrolytic plasma nitriding. Thus, studies have demonstrated the feasibility and applicability of electrolytic-plasma nitriding in order to improve cutting tools work resource, working under friction and wear conditions.

In this paper microstructure, morphology, elemental composition, phase composition and crystal structure of the sample steel R6M5 were investigate by using the methods of scanning electron microscopy, electron backscatter diffraction (EBSD) analysis and X-ray diffraction (XRD) analysis. Determined that the microstructure of steel R6M5 after hardening and three-time tempering consists of tempered martensite and solid carbide M6C and MC-type with spherical shape and a diameter of less than 3 μm. Detected that the volume fraction of each carbide amounted to 10.4±0.6% and 2.3±0.4% - for grey and bright carbides, respectively, and that the sizes of bright carbides particles in the microstructure of steel R6M5 are 0.4-4,5 μm, and the sizes of grey carbides particles are 0.5-1.1 μm. XRD analysis showed that the main carbides in the studied steel are carbides М6С and MC, which have complicated the FCC crystal lattice and the Fd3m spatial group. Determined that carbides are uniform and monocrystalline. ESBD analysis with the support of the XRD analysis showed that carbides spherical shape М6С fit to Fe3W3C composition.

Developed a new method of electrolytic-plasma nitriding, which enable to carry out surface modification of high-speed steels and provide the high kinetic energy efficiency of diffusion saturation process. . Implementation of electrolytic-plasma nitriding of high-speed steel R6M5 in the optimal mode was determined, which leads to a significant increase in hardness and wear-resistance of the high-speed steel surface layer. It is experimentally established, that after nitriding of electrolytic-plasma heating on the surface of high-speed steel R6M5 formed the modified layer, which has high abrasive wear resistance as compared with the source material.

This paper presents research of influence electrolyte plasma carbonitriding on tribological properties of R6M5 high-speed steel. Shows perspectiveness of carbonitriding high-speed steels in electrolyte plasma. The results of research demonstrated increasing wear-resistance of R6M5 steel after carbonitriding in electrolyte plasma. Under the same test conditions by the method of scratch-test have been determined that the depth of the scar of a modified layer has become less in comparison with the original sample, which indicates a significant increase of wear-resistance and hardness of the surface carbonitriding layer R6М5 steel. It was set that after electrolytic-plasma carbonitriding abrasive wear-resistance of the surface layers of R6M5 steel is increased by 25%. Introduction

Mechanical characteristics of nitrated and carbonitriding in electrolyte plasma steel Р6М5 surface layers are investigated in the research. It shows perspectiveness of the cutting tool electrolyte-plasma treatment technology. Comparative research of structure, phase composition of fast-cutting P6M5 steel modified surface layers after electrolyte plasma treatment was carried out by scanning-electron and light microscopy, and X-ray structure analysis methods.

Microhardness of nitrated and carbonitriding in electrolyte plasma steel Р6М5 surface layers are investigated in the research. It shows perspectiveness of the cutting tool electrolyte-plasma treatment technology. Operating conditions for the technology realization are defined. It was also indicated the desired content of components in saturating mixtures by nitriding and carbonitriding. Comparative research of structure, phase composition of fast-cutting P6M5 steel modified surface layers after electrolyte plasma treatment was carried out by scanning-electron and light microscopy, and X-ray structure analysis methods. The way of electrolytic plasma nitriding in cathodic mode, to provide fast-cutting steels which allows for modification the surface and high kinetic efficiency the process diffusion saturation. It was established that as a result of nitriding and nitrocarburizing in plasma electrolyte has been a significant increase in microhardness in the surface layers of steel Р6M5.