Nitration of machine parts with production of nanostructured surface ply and ply composition |
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IPC classes for russian patent Nitration of machine parts with production of nanostructured surface ply and ply composition (RU 2522872):
Method of increasing resistance of steel pipelines against corrosion by case-hardening / 2488649
Method of steel pipe case-hardening comprises heating to 1200-1400°C in carbon-bearing medium in arc flame between two graphite electrodes of arc torch, curing and cooling. Pipe surface is heated for 5-25 s. Current of 50-250 A is fed to electrodes. Arc flame is displaced on pipe surface in helical line at the rate of 2-20 mm/s and pitch of 0.75-0.8 of heating spot diameter making 20-25 mm. Pipe surface is arranged 10 mm from electrode ends in carbon arc flame area. Pipe surface heated by electric arc at 75-100 mm from arc flame is water cooled. In case-hardening, pressure in pipe is kept at the level of 0.5-0.75 of operating pressure. Pipe surface coat features excellent resistance due to it rules out penetration of atomic hydrogen into steel and boats hardness of 2000 N/mm2.
Method to process long steel part / 2455386
Long steel part is processed. During processing the preliminary and final ion-vacuum nitriding in a glow discharge, restriking and honing are carried out. Restriking and honing are carried out after the preliminary and before the final nitriding, at that the preliminary nitriding is performed at a temperature of 510-530°C and a pressure of 350-600 Pa during 8-14 hours. The final nitriding is performed at a temperature of 500-540°C for 2.0-4.0 hours and a pressure of 390-650 Pa.
 Plant for vacuum ion-plasma treatment of long components / 2450083
Plant contains vacuum chamber 1 with component holder 12 with insulated current lead and at least one long electrode 2 of arc plasma source; device for components heating and power supply units for vacuum-arc discharge 3 and component heating device 11. Component heating device 11 is an additional emission chamber 7 insulated by screens and insulators; inside this chamber there is long cathode 8 of vacuum-arc discharge which is electron emitter; emission chamber 7 is connected with vacuum chamber 1 by perforated partition 9 at that perforated holes 10 are located along longitudinal cathode axis 8 of vacuum-arc discharge. At that power supply unit 11 for component heating device has an option of connection to negative pole of emission chamber while positive pole is connected to component holder 12 or electrode 2. Power supply unit 3 of vacuum-arc discharge has an option of connection to negative pole of cathode 8 of vacuum-arc discharge or electrode 2, while positive pole can be connected to emission chamber 7 or vacuum chamber 1.
 Method of obtaining products / 2440794
Invention relates to method of obtaining products from titanium-based material with coating, representing semi-spherical head of medical semi-spherical cutter. Workpiece from unalloyed titanium is made by cold sheet-stamping stamping and drilling holes with countersinking. Hole centres are placed on two spiral lines with left approach, converging in dome, with obtaining semi-spherical head of medical cutter. External head surface is polished to roughness Ra not more than 0.1 mcm and cutting elements are made by flanging sharpened edges from left side of holes outwards and their sharpening. Nitration with vacuum ion-plasma method to the depth not less than 50 mcm is carried out. Titanium nitrade TiN layers are precipitated until total thickness of said layers is 4-7 mcm with microhardness more than 7000 MPa.
Procedure for ion-vacuum chemical-thermal treatment of steel part with threaded surface / 2428504
Procedure consists in part heating, in nitriding during heating in nitrogen containing gas from 390 - 410°C to 500 - 570°C during 1 - 4 hours and in cooling from 500 - 570°C to 350 - 400°C during 40 - 60 minutes in plasma of glowing discharge directly upon heating.
 Procedure for strengthening surface of items of titanium alloys / 2427666
Here is claimed procedure for strengthening items of titanium alloys. The procedure consists in heating surface of an item in nitrogen medium; also, heating is performed with a concentrated heat source with density of power 103-104 Wt/cm2, current strength 80-150 A and rate of source transfer relative to an item - 0.005-0.01 m/sec.
Procedure for ion-vacuum nitriding long-length steel part in glow discharge / 2419676
Invention can be used for treatment of long-length precision cylinders of well pumps operating under abrasive wear conditions. The procedure for ion-vacuum nitriding long-length steel part in glow discharge consists in heating part at temperature 400-450°C, in isothermal conditioning during 20-30 minutes, in preliminary nitriding at temperature 480-510°C for 60-120 minutes, in final nitriding at temperature 20-50°C above temperature of preliminary nitriding during 8-16 hours and in cooling to 350-400°C during 40-60 minutes.
 Procedure for creation of macro non-uniform structure of material at nitriding / 2418096
Procedure for treatment of parts out of titanium alloys consists in cathode sputtering and nitriding. Before and after nitriding parts are annealed in vacuum. For nitriding there is supplied mixture of gases consisting of 10 wt % of nitrogen and 90 wt % of argon. Further, parts are vacuum heated in non-uniform plasma of higher density which is created between a part and a screen due to effect of a hollow cathode. Thus there is facilitated formation of regular macro non-uniform structure. Structure of cells of the screen is honeycomb-like. Parts are annealed before and after nitriding at temperature 800°C during 2 hours, while nitriding is carried out at temperature below α→β of transition of titanium alloy.
 Procedure for vacuum ion-plasma nitriding items out of steel / 2418095
Procedure consists in vacuum heating items in plasma of nitrogen of higher density. Plasma of nitrogen of higher density is generated in toroid region of electron motion formed with crossed electric and magnetic fields. Under effect of magnetic field created with two cylinder magnets one of which is hollow, electrons move along cycloid closed trajectories.
Procedure for plasma boriding / 2415965
Procedure for plasma boriding metal surface out of titanium, of ally on base of titanium, of steel or of ferrochromium consists in introducing KBH4 into reaction chamber, where H corresponds to halogen. KBH4 is heated to temperature sufficient for release of BH3. BH3 is subjected to plasma discharge. There are generated activated boron containing particles diffused in metal surface. In an alternative procedure of the invention KBH4 is thermally decomposed producing KH and BH3. BH3 is directed to plasma formed with inert gas. Also, composition and conditions of plasma generation are selected to facilitate decomposition of BH3 into BH2 + and H. BH2 + is diffused into metal surface.
 Method of forming epitaxial copper nanostructures on surface of semiconductor substrates / 2522844
Method of forming epitaxial copper nanostructures on the surface of semiconductor substrates includes formation of a monoatomic layer of copper silicide Cu2Si on a preliminarily prepared atomically clean surface of Si(111)7×7 at a temperature of 550-600°C under conditions of superhigh vacuum, further precipitation of copper on it at a temperature of 500-550°C with efficient copper thickness from 0.4 to 2.5 nm. With efficient copper thickness from 0.4 to 0.8 nm islands of epitaxial copper nanostructures of a triangular and polygonal shape are formed, and if copper thickness is in the range from 0.8 to 2.5 nm, in addition to copper islands of the triangular and polygonal shapes ideally even copper wires are formed. The formed epitaxial copper nanostructures possess faceting, are oriented along crystallographic directions <110>Cu||<112>Si.
 Nanotechnological complex / 2522776
Invention relates to nanotechnology equipment and designed for closed cycle of production and measurement of new products of nanoelectronics. The nanotechnological complex comprises a robot-distributor with the ability of axial rotation, coupled with the chamber of loading samples and the module of local influence, as well as the measuring module comprising a scanning probe microscope, an analytical chamber, a monochromator and an x-ray source. The measuring module and the analytical chamber are coupled with the robot-dispenser, the monochromator is coupled with the analytical chamber, and the x-ray source - with the monochromator. The module of local influence comprises a module of focused ion beams and the first scanning electron microscope.
 Electric sensor for hydrazine vapours / 2522735
Electric sensor for hydrazine vapours contains a dielectric substrate, on which placed are: electrodes and a sensitive layer, which changes photoconductivity as a result of hydrazine vapour adsorption; the sensitive layer consists of the following structure - graphene-semiconductor quantum dots, whose photoconductivity decreases when hydrazine molecules are adsorbed on the surface of quantum dots proportionally to the concentration of hydrazine vapour in a sample. If hydrazine vapours are present in the air sample, hydrazine molecules are adsorbed on the surface of quantum dots, decreasing intensity of quantum dot luminescence, which results in decrease of graphene conductivity proportionally to the concentration of hydrazine vapours in the analysed sample.
 Diagnostics of flaws on metal surfaces / 2522709
Gold cylindrical nanoparticles not over 100 nm in length are sprayed onto surface of tested object, depth of the ply of said particles allowing the filling of cavities of would-be fractures. Then, said surface is dried to remove sprayed ply therefrom. Then, object surface is subjected to non-interlaced scan by fs-laser beam. At a time, intensity of two-photon luminescence signal is registered in every area under analysis to fix the location of said area corresponding to object coordinate. 2D array of two-photon luminescence signal intensities is formed to produce the map of distribution of nanoparticle luminescence intensities excited by laser radiation.
 Microwave plasma converter / 2522636
Invention may be used when producing carbon nanotubes and hydrogen. Microwave plasma converter comprises flow reactor 1 of radiotransparent heat-resistant material, filled with gas permeable electrically conductive material - catalyst 2 placed into the ultrahigh frequency waveguide 3 connected to the microwave electromagnetic radiation source 5, provided with microwave electromagnetic field concentrator, designed in the form of waveguide-coax junction (WCJ) 8 with hollow outer and inner conductors 9, forming discharge chamber 11 and secondary discharge system. Auxiliary discharge system is designed from N discharge devices 12, where N is greater than 1, arranged in a cross-sectional plane of discharge chamber 11 uniformly in circumferential direction. Longitudinal axes of discharge devices 12 are oriented tangentially with respect to the side surface of discharge chamber 11 in one direction. Nozzle 10 is made at outlet end of inner hollow conductor 9 of WCJ 8 coaxial. Each of discharge devices 12 is provided with individual gas pipeline 13 to supply plasma-supporting gas to discharge zone.
 Method of determining angle of misorientation of diamond crystallites in diamond composite / 2522596
Invention can be used in the field of elaboration of diamond-based materials for magnetic therapy, quantum optics and medicine. A method of determining an angle of misorientation of diamond crystallites in a diamond composite includes placement of the diamond composite into a resonator of an electronic paramagnetic resonance (EPR) spectrometer, measurement of EPR spectrums of nitrogen-vacancy NV-defect in the diamond composite with different orientations of the diamond composite relative to the external magnetic field, comparison of the obtained dependences of EPR lines with the calculated positions of EPR lines of NV-defect in the diamond monocrystal in the magnetic field, determined by the calculation. After that, the angle of misorientation of the diamond crystallites is determined by an increase of width of EPR line in the diamond composite in comparison with the width of EPR line in the diamond monocrystal.
 Method of modifying envelopes of polyelectrolyte capsules with magnetite nanoparticles / 2522204
Invention relates to a method of modifying envelopes of polyelectrolyte capsules with magnetite nanoparticles. The disclosed method involves producing a container matrix in form of porous calcium carbonate microparticles, forming envelopes of polyelectrolyte capsules by successive adsorption of polyallyl amine and polystyrene sulphonate and modifying with magnetite nanoparticles on the surface of the container matrix or after dissolving the matrix through synthesis of magnetite nanoparticles via chemical condensation.
 Method of producing nanostructured metal oxide coatings / 2521643
Method comprises preparing an alcohol solution of β-diketonates of one or more p-, d- or f-metals with concentration 0.001h2 mol/l; heating the solution to 368-523 K and holding at said temperature for 10-360 minutes to form a metal alkoxo-β-diketonate solution; depositing the obtained solution in droplets at the centre of a substrate being rotated at a rate of 100-16000 rpm, or immersing the substrate into said solution at a rate of 0.1-1000 mm/min at an angle of 0-60° to the vertical; holding the substrate with a film of the alkoxo-β-diketonate solution at 77-523 K until mass loss ceases, to form xerogel on the surface of the substrate; crystallising oxide from the xerogel at 573-1773 K.
 Method for preparing nanodiamonds with methane pyrolysis in electric field / 2521581
Invention may be used in medicine in producing preparations for a postoperative supporting therapy. What is involved is the high-temperature decomposition of methane on silicone or nickel substrate under pressure of 10-30 tor and a temperature of 1050-1150°C. The heating is conducted by passing the electric current through a carbon foil, cloth, felt or a structural graphite plate whereon the substrates are arranged. An analogous plate whereon a displacement potential from an external source is sent is placed above the specified plate. Nanodiamonds of 4 nm to 10 nm in size are deposited on the substrates.
 Agent with anti-stroke action, and method for preparing it / 2521404
Invention concerns an agent having an anti-stroke action and representing the amino acid glycine immobilised on the detonation-synthesised nanodiamond particles of 2-10 nm in size, and a method for preparing it.
 Nanoliposome with application of etherificated lecitin and method of obtaining such, as well as composition for prevention or treatment of skin diseases including such liposomes / 2418575
Invention relates to medicine and deals with nanoliposome which includes liposomal membrane, contains ethgerificated lecitin and one or more physiologically active ingredients, incorporated in the internal space of liposomal membrane, method of obtaining such, as well as composition for prevention or treatment of skin diseases, containing nanoliposome.
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FIELD: process engineering. SUBSTANCE: invention relates to metallurgy. Parts are processed by quenching at 920-940°C, subjected to negative hardening with heating to 600-650°C for 2-10 hours and removal of decarbonised ply. Then, ion-plasma nitration is performed at 500-570°C, cathode voltage of 300-320 V, and current density of 0.20-0.23 mA/cm2. Ammonia with dissociation of 0-80% is used as a gas medium. Ammonia flow rate makes up to 20 dm3/h. Pressure in the chamber at cathode spraying makes 1.3-1.35 Pa and, at saturation, 5-8 GPa. This nitration is performed at cyclic temperature and ammonia dissociation variation. Note here that at the first half of described cycle temperature makes 570°C at maximum nitrogen potential. During second half, temperature decreases to 500°C while nitrogen potential is decreased owing to increase in ammonia dissociation to 40-80%. Note also that the number of said cycles should make at least 10. Nitrated part has surface ply containing diffusion ply with α-phase with nanosized incoherent alloying element nitrides that makes soft matrix. Besides, it has surface ply with hard inclusions composed by nanoparticles of ε-phase iron nitrides formed by local phase recrystallisation of iron nitride lattices. This results from cyclic temperature and ammonia dissociation variation. EFFECT: higher wear resistance, longer life of kinetic friction parts made from above described material. 2 cl, 1 tbl, 2 dwg
The technical field The invention relates to mechanical engineering, in particular to a method of nitriding of machine parts with obtaining nanostructured surface layer, the nanostructure state diffusion layers used to improve wear resistance of parts sliding friction units of alloys based on iron. The level of technology Known methods of chemical-heat treatment that can improve the wear resistance of steel parts and contains the operations of preliminary heat treatment and subsequent nitriding. Thus, the technical solution contained in (RF Patent No. 2291227, IPC C23F 17/00, C23C 8/26, C21D 1/72, publ. 10.01.2007), calls for before nitriding pretreatment, consisting of the following operations: normalizing, tempering, hardening, tempering, machining, stabilizing vacation, and then nitriding at a temperature of 530°C for 1.5 to 30 h and diazotoluene within 0,4 1,5 hours...This method allows to increase wear resistance and reduce the fragility of the near-surface layers of steel, however, the mechanical properties of the surface have a fairly large scatter (according to the description of the patent it is not less than 15%), and the process of nanostructuring in the diffusion zone does not occur. As a result, the improvement of wear resistance remains within the Ah, defined through the wear rate of the Ihnot more than Ih≈10-9. There is also known a method of processing steel products in gaseous environment (Patent RF №2367716, IPC C23C 8/34, C23C 8/26, publ. 20.09.2009), including heating products to the saturation temperature of 450...780°C in an atmosphere of ammonia, followed by exposure to saturating gaseous environment, where as saturating the environment with a shutter speed using the air and ammonia, which are served separately, and the exposure of the products are performed alternately in air and then in an atmosphere of ammonia with the formation on the surface of a multilayer structure consisting of alternating between the layers of oxide and nitride phases of iron and the respective alloying elements. However, the oxide layer has a low mechanical properties and low wear resistance, it reduces the overall effect of improving wear resistance. The closest technical solution is a method of chemical-heat treatment described in (Patent RF №2367715, IPC C23C 8/34, C23C 8/26, publ. 20.09.2009). The main difference of this method is the use of air atmosphere for forming on the surface of the steel before nitriding layer of oxides. The sequence of operations in this way is as follows: heating in an inert atmosphere, the exposure at the attained temperature is ur in air atmosphere, exposure to saturating nitrogen-containing atmosphere to obtain a diffusion layer in the form of nanoparticles of nitrides of alloying elements. The main disadvantage of this method is the presence of the oxide layer, which according to the authors of the present invention, the analog promotes the penetration of nitrogen into the steel and the formation of nanoparticles of special nitrides. This way, nano-sized particles of nitrides. However, the resulting composite oxide-nitride layer is not effective - insufficient wear - improving the wear resistance is negligible within - the order of tens of percent. Disclosure of inventions The task of the invention is a significant improvement of wear resistance of the surface layers formed in the nitriding parts sliding friction units, and a corresponding increase in the durability of sliding friction units with the same composition of the surface layer. The technical effect is achieved in that in the method of nitriding parts sliding friction units with obtaining nanostructured surface layer part is subjected to a preliminary heat treatment and subsequent nitriding. At the same time as the preliminary heat treatment using a tempering at a temperature of 920...940°C, subsequent high the vacation up to 600...650°C for 2...10 hours and removal of de-carbonized layer, and then spend a plasma nitriding process with the following parameters in the temperature range of 500 to 570°With: - the voltage at the cathode 300...320V; - current density of 0.20...0,23 mA/cm2; - the composition of the gas medium, the ammonia with the degree of dissociation from zero to 80%; - the consumption of ammonia to 20 DM3/h; - the pressure in the chamber at the cathode sputtering - 1,3 1,35...PA, at saturation - 5...8 GPA. Moreover, the nitriding is carried out in the mode of cyclic changes of temperature and degree of dissociation of ammonia in the first half of the cycle the temperature is 570°C at maximum nitrogen potential, but in the second half of the cycle, the temperature was lowered to 500°C, while the nitrogen potential is reduced by increasing the degree of dissociation of ammonia (40...80%), while the number of such cycles must be at least 10. Detail of the friction slip with nanostructured surface layer includes a diffusion zone with nanoscale nitride inclusions, while considered nanostructured surface layer obtained by the proposed method contains a diffusion layer with an α-phase with nanoscale non-coherent nitrides of alloying elements, which forms a soft matrix, and the surface layer containing solid particles constituting the nanoparticles of iron nitrides : ε-phase generated by the phase of the local recrystallization p is setok nitrides of iron, which is provided by cyclic change of temperature nitriding and the degree of dissociation of ammonia. List of drawings Figure 1 shows the microstructure of the ε-phase in the upper part of the nitrided layer steel MOI: - svetlopoli image microdiffraction pattern. (d) dark-field image of the ε-phase in the reflex (110); figure 2 - change in the wear rate nitrided steel MOA at sliding friction. The implementation of the invention The main difference of the proposed method of treatment is that there is a formation of a diffusion zone with nitrides of alloying elements having a non-coherent link with the matrix and the size 10...15 nm, and the surface layer, consisting of nanoparticles ε-phase of iron nitrides of Fe2-3N) of size 20...50 nm. The nitriding is carried out in conditions of cyclic changes of temperature nitriding and supply of ammonia with different (from 0 to 80%) degree of dissociation, which allows the process to change the nitrogen potential of the gas environment. As a result of this process of reception (Cycling) in the proposed solution the conditions for phase recrystallization of the nitrided zone and its formation in nanostructured state. On the first active stage of the cycle at a temperature of 570°C in flowing ammonia in the conditions is x high nitrogen capacity created a fairly thick (20...30 µm) nitride layer of the ε - and γ'-phases, phases of nitrides of iron and alloying elements formed by direct recrystallization of the α↔γ'↔ε. The second passive stage of the cycle, the temperature was lowered to 500°C. and for a time served dissociatively ammonia (degree of dissociation from 40 to 80%). A sharp decrease in nitrogen capacity caused the development of reverse transformation ε↔γ'. When the alternation of cycles, consisting of active and passive stages, grinding patterns nitride zone and the formation of surface nitriding steels surface layer of ε-phase in the nanostructured state. The layer thickness of the ε-phase, the size of the crystals in it, and their hardness is substantially influenced by the temperature of the preliminary (before nitriding) high holidays. At one and the same mode of nitriding layer thickness ε-phase increases in proportion to the increase in the tempering temperature of 500 to 650°C. in Addition, the reduced nano-sized nitrides in this phase, increases their hardness and, consequently, increases its durability. Plasma nitriding process, giving the possibility to adjust the parameters of the technological process, carried out under the following parameters in the temperature range of 500 to 570°C: the voltage at the cathode 300 320...; the current density of 0.20...0,23 mA/cm2; the composition of the gas environment - ammonia varying degrees of dissoc the purpose (range from 0 to 80%; the flow rate of the gas mixture to 20 DM3/h; - pressure in the chamber at the cathode sputtering - 1,3 1,35...PA at saturation - 5...8 GPA. Modes nitriding and parameters of the surface layer are shown in table 1.
The rationale for the number of cycles contained in the table, where it is shown that the thickness of the nanostructured layer (layer ε-phase) may be not less than 10 μm when the number of cycles of at least 10, and provides the necessary wear resistance of the surface layer. The nitrided layer has a layered and multi-phase structure. It is accepted that the work surface should have a structure which Assenova nitrogen solid solution with particles of nitrides of alloying elements. Surface nitride zone nitrided layer in the form of the ε-phase is traditionally removed by grinding details. Meanwhile, the results of the studies indicate that when certain established authors modes of ion-plasma nitriding layer ε-phase is formed in the form of nanocrystalline particles. The formation of the ε-phase in the nanostructured state is confirmed by x-ray diffraction and electron microscopic studies. Used a special technique of moving the x-ray beam. Shooting at a small angle to the analyzed surface was provided information about the structure of the thin layer of ε-phase. Physical broadening of x-ray lines clearly demonstrated that the ε-phase is nanocrystalline with crystals size from 20 to 50 nm, which is confirmed by the results of transmission electron microscopy (figure 1). First it is shown that the basis for the creation of nanoscale structures is phase recrystallization: ε↔γ'↔α phase nitrided layer, a driving force which is changing during the process, the nitrogen capacity of the gas environment. The mechanism of recrystallization causes the formation of nuclei of crystals of the new phase within the existing (old) phase. Solid-phase local recrystallization of lattices nitri the s iron based on the simultaneous nucleation and growth of five "doubles" on stable nitrogen atom icosahedral clusters. In conditions of cyclic change the value of the nitrogen potential of developing multiple phase recrystallization and the surface is formed nanostructured nitride layer with a crystal size of 50 nm. It is important that the nanostructured layer is formed directly on the surface of the hardened parts during the nitriding process. This is a significant advantage of the phase recrystallization as a way of intensive grinding of grain and increase the wear resistance of sliding friction units. Experience of experimental research shows that in the diffusion zone formed a special nitride (nitride alloying elements). Depending on the technology parameters of these nitrides have a coherent, poluchennuyu and incoherent communication with the matrix, their size has a nanometer scale. They provide a strengthening effect and correspondingly increased durability. The authors found that the greatest effect of improving wear resistance of material couples the sliding friction provide nitrides, no coherent or polutoraletnej connection with the matrix, i.e. incoherent nitrides of alloying elements. This effect is the effect of nanocrystalline surface layer (ε-phase), which represents an increase of wear resistance n is 2 orders of magnitude (100 times). When this diffusion zone with incoherent particles plays the role of a soft substrate for solid particles ε-phase, which creates favorable conditions for the process of deformation by friction with a minimum level of destruction. Conducted long-term tests of pairs of sliding friction. Set that layer ε-nitride, located in the nanocrystalline state, has the practical effect of bezsennosc. Weight loss of the samples with a layer of ε-phase is at the limit of sensitivity of the recording equipment. As an example, figure 2 shows the kinetic curves of wear diffusion zone with non-coherent nitrides of alloying elements and the surface layer, consisting of ε-phase, when the sliding friction with the average relative sliding speed v=0,19 m/s and pressure in contact with p=10 MPa (line 1 - wear diffusion zone containing a special nitride (nitride alloying elements), incoherent with the matrix, line 2 - the wear of the surface layer above the diffusion zone and consisting of ε-nitride (Fe2-3N) in the nanocrystalline state. It is seen that the wear layer of nanocrystalline ε-phase two orders of magnitude lower. Calculations show that even durability only this layer is sufficient to ensure the endurance of many of sliding friction units, including cervical shafts, to lucky camshafts, plunger pairs, injector of diesel engines. Thus, the technical result of the proposed solutions reduce the wear rate of parts sliding friction units two orders of magnitude (100 times). The method can be used in the composition of the set of processing operations in the manufacture of machine parts involved in the sliding friction and prone to wear. Therefore, the combination of a number of known characteristics, namely the conduct of the pre-nitriding heat treatment (high holidays), and then ion-plasma nitriding with the cyclic change of the mode, temperature and nitrogen potential of the gas environment allows you to get a new synergetic effect, consisting in the formation of a diffusion zone with non-coherent nitride and the surface layer with particles of ε-phase (Fe2-3N) in the nanocrystalline state and multiple (2) improving the wear resistance of the parts being processed. 1. Method of nitriding parts sliding friction units with obtaining nanostructured surface layer comprising a pre-heat treatment and subsequent nitriding parts, characterized in that as a preliminary heat treatment using a tempering at a temperature of 920-940°C, the subsequent high-temperature tempering up to 600-650°C during the course the e 2-10 hours and removal of de-carbonized layer, then spend a plasma nitriding process in the temperature range 500-570°C when the voltage at the cathode 300-320 B, current density of 0.20-0.23mm mA/cm2when used as a gas environment of ammonia with the degree of dissociation from zero to 80%, the flow rate of ammonia to 20 DM3/h, the pressure in the chamber at the cathode sputtering 1,3-1,35 PA, at saturation 5-8 GPA, while the nitriding is carried out in the mode of cyclic changes of temperature and degree of dissociation of ammonia in the first half of the cycle the temperature is 570°C at maximum nitrogen potential, but in the second half of the cycle, the temperature was lowered to 500°C, with nitrogen capacity reduced by increasing the degree of dissociation of ammonia up to 40-80%, while the number of cycles mentioned should not be less than 10. 2. Detail of the friction slip with nanostructured surface layer containing a diffusion zone with nanoscale nitride inclusions, characterized in that the surface layer obtained by the method according to claim 1, in fact the nanostructured surface layer includes a diffusion layer with an α-phase with nanoscale non-coherent nitrides of alloying elements, which forms a soft matrix, and the surface layer containing solid particles constituting the nanoparticles of iron nitrides : ε-phase generated by the phase the th local recrystallization gratings of iron nitrides, which is provided by cyclic change of temperature nitriding and the degree of dissociation of ammonia.
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