The analysis of ways to increase the durability of shut-off valves loaded elements

2021 ◽  
Vol 6 (3) ◽  
pp. 225-235
Author(s):  
Islam A. Alexandrov ◽  
Alexander N. Muranov ◽  
Maxim S. Mikhailov
Keyword(s):  
Wear Resistance ◽  
Surface Modification ◽  
Structural Phase ◽  
Oil And Gas Industry ◽  
Vacuum Arc ◽  
Technical Equipment ◽  
Functional Coatings ◽  
Functional Coating ◽  
Mechanical Methods ◽  
Contact Surfaces

This review analyzes the problems caused by heavy wear of loaded friction elements of structures, which is typical of almost all industries. This implies the importance of solving problems of increasing their durability. Of particular relevance is the need to solve the problem of improving wear resistance of contact surfaces of special-purpose shut-off valves, being an irreplaceable component of technical equipment used in the oil and gas industry as well as processing industries, nuclear energy, and medicine. It is shown that the effectiveness of solving problems of increasing durability of equipment is largely associated with additional standard processing of loaded friction elements of such structures, and with the improvement of technologies for increasing wear resistance and strength characteristics of their contact surfaces. The analysis of the possibilities of increasing wear resistance by mechanical methods of surface treatment, as well as by methods of surface modification through various functional coatings has been made. It is substantiated that the vacuum-arc method of ion-plasma spraying of a multilayer nanocomposite coating is the most promising way of creating a functional coating to increase the wear resistance of valves. Widespread industrial introduction of the method of beam surface modification of materials makes it possible to obtain such structural-phase states of materials, which are not possible with traditional methods.

scholarly journals Aluminum surface modification by electron-ion-plasma methods

2018 ◽  
Vol 143 ◽  
pp. 03007 ◽  
Author(s):  
Olga Krysina ◽  
Elizaveta Petrikova ◽  
Vladimir Shugurov ◽  
Pavel Moskvin ◽  
Yurii Ivanov
Keyword(s):  
Wear Resistance ◽  
Electron Beam ◽  
Plasma Treatment ◽  
Pure Aluminum ◽  
Structural Phase ◽  
Vacuum Arc ◽  
Aluminum Surface ◽  
Titanium Coating ◽  
Commercially Pure ◽  
Ion Plasma

The paper focuses on detection and structural-phase justification of the modes of combined electron-ion plasma treatment of commercially pure A7 grade aluminum carried out in a single vacuum cycle and enabling to enhance mechanical (microhardness) and tribological (wear resistance) properties of the material. Commercially pure A7 grade aluminum underwent combined surface treatment, including deposition of titanium coating by means of vacuum-arc technique and further mixing of the coating/substrate system by intense pulsed electron beam. The varied parameters were energy density of the electron beam (10, 15, 20) J/cm2 and the number of impact pulses (3-100); the thickness of titanium coating was 0.5 μm. Electron-ion plasma treatment of aluminum was carried out in a single vacuum cycle. Optical and scanning electron microscope investigations, measuring of microhardness and tribological tests allowed defining the modes when hardness and wear resistance of the modified surface layer increases manifold in comparison to the initial properties of commercially pure aluminum.

Effect of cluster-gradient architecture of nanostructured topocomposites on features of tribointeraction with heterophased material

2020 ◽  
pp. 130-135
Author(s):  
D.N. Korotaev ◽  
K.N. Poleshchenko ◽  
E.N. Eremin ◽  
E.E. Tarasov
Keyword(s):  
Wear Resistance ◽  
Titanium Alloy ◽  
Energy Dissipation ◽  
Phase Structure ◽  
Diffusion Processes ◽  
Structural Phase ◽  
High Wear Resistance ◽  
Wear Characteristics ◽  
And Diffusion

The wear resistance and wear characteristics of cluster-gradient architecture (CGA) nanostructured topocomposites are studied. The specifics of tribocontact interaction under microcutting conditions is considered. The reasons for retention of high wear resistance of this class of nanostructured topocomposites are studied. The mechanisms of energy dissipation from the tribocontact zone, due to the nanogeometry and the structural-phase structure of CGA topocomposites are analyzed. The role of triboactivated deformation and diffusion processes in providing increased wear resistance of carbide-based topocomposites is shown. They are tested under the conditions of blade processing of heat-resistant titanium alloy.

Improving surface finish and wear resistance of additive manufactured nickel-titanium by ultrasonic nano-crystal surface modification

2017 ◽  
Vol 249 ◽  
pp. 433-440 ◽  
Author(s):  
Chi Ma ◽  
Mohsen Taheri Andani ◽  
Haifeng Qin ◽  
Narges Shayesteh Moghaddam ◽  
Hamdy Ibrahim ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Surface Modification ◽  
Surface Finish ◽  
Crystal Surface ◽  
Nickel Titanium ◽  
Nano Crystal

Reduction in Wear Rate of α-Alumina and Silicon Nitride by Diffusional Surface Modification

1988 ◽  
Vol 140 ◽  
Author(s):  
A.K. Gangopadhyay ◽  
M.E. Fine ◽  
H.S. Cheng
Keyword(s):  
Wear Resistance ◽  
Thermal Expansion ◽  
Surface Modification ◽  
Silicon Nitride ◽  
Thermal Expansion Coefficient ◽  
Expansion Coefficient ◽  
Surface Region ◽  
Lattice Parameter ◽  
Lower Thermal Expansion ◽  
Wear Modes

AbstractThe surface regions of α-alumina and hot pressed silicon nitride were modified by suitable alloying in order to improve their wear resistance. The surface modification in polycrystalline α-alumina was done by diffusing chromia into the surface region which resulted in the formation of a thin layer of A12O3 - Cr9O3 solid solution which has a lower thermal expansion coefficient than pure α-alumina. Also Cr2O3 has a larger lattice parameter than α-alumina thus during cooling the surface was put into compression. The surface region of hot pressed silicon nitride was modified by diffusing α-alumina into the surface which resulted in the formation of a thin sialon layer. A surface compressive stress was again introduced due to the lower thermal expansion coefficient and larger latticeparameter of sialon compared to silicon nitride.Wear tests were conducted against 52100 steel under both lubricated and unlubricated sliding contact using a block on ring apparatus. The wear resistance of chromia surface alloyed α-alumina was improved considerably over unalloyed α-alumina under both lubricated and unlubricated conditions. The wear resistance of alumina surface alloyed silicon nitride was also improved over unalloyed silicon nitride under both lubricated and unlubricated conditions.Different wear modes were identified by examining the worn surfaces under the scanning electron microscope.

Innovative research carried out at the nanocenter of the NRC “Kurchatov Institute” – CRISM “Prometey”

2021 ◽  
pp. 82-108
Author(s):  
T. I. Bobkova ◽  
R. Yu. Bystrov ◽  
O. V. Vasilieva ◽  
A. F. Vasiliev ◽  
D. A. Gerashchenkov ◽  
...  
Keyword(s):  
Surface Modification ◽  
Composite Materials ◽  
Magnetron Sputtering ◽  
Alternative Energy ◽  
Technical Equipment ◽  
Structural Ceramics ◽  
Kurchatov Institute ◽  
Biological Objects ◽  
The Past ◽  
Innovative Research

This article presents the results of comprehensive innovative research carried out over the past 15 years at the Nanocenter of the NRC “Kurchatov Institute” – CRISM “Prometey” in the following areas: the creation of coatings based on quasicrystals of the Al-Cu-Fe system, laser synthesis technologies, systems electromagnetic protection of technical equipment and biological objects, structural ceramics and composite materials, technologies for surface modification and magnetron sputtering, obtaining powders by melt spraying, hydrogen and alternative energy.

Surface modification of die steels with B—Al-layers by thermal-chemical treatment

2021 ◽  
pp. 557-564
Author(s):  
N.S. Ulakhanov ◽  
U.L. Mishigdorzhiyn ◽  
A.G. Tikhonov ◽  
A.I. Shustov ◽  
A.S. Pyatykh
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
Surface Layer ◽  
Surface Modification ◽  
High Temperature ◽  
Chemical Treatment ◽  
Quality Parameters ◽  
Processing Temperature ◽  
Die Steels ◽  
Composite Layers

The effect of diffusion high-temperature boroaluminizing (HBA) on the mechanical properties and quality parameters of the surface layer of stamp steels 5KhNM and 3Kh2V8F is shown. An analysis of the microstructure and composition of diffusion composite layers obtained as a result of thermal-chemical treatment (TCT) is presented and the distribution of microhardness in these layers is studied depending on the formed borides and carbides. The influence of processing temperature modes of on the parameters of roughness was experimentally established and the wear resistance characteristics of the processed surfaces of the investigated materials were determined.

COMPARISON OF WEAR RESISTANCE MECHANISMS OF DIE STEEL IMPLANTED WITH C AND Mo IONS

2007 ◽  
Vol 14 (03) ◽  
pp. 517-520
Author(s):  
M. F. CHENG ◽  
J. H. YANG ◽  
X. D. LUO ◽  
T. H. ZHANG
Keyword(s):  
Wear Resistance ◽  
Ion Implantation ◽  
Photoelectron Spectroscopy ◽  
Grazing Angle ◽  
Resistance Mechanisms ◽  
Ion Source ◽  
Vacuum Arc ◽  
H13 Steel ◽  
Die Steel ◽  
X Ray

Mo and C ions extracted from a metal vapor vacuum arc ion source were implanted into the surface of die steel (H13) to compare the wear resistance mechanisms of the implanted samples, respectively. The concentration depth profiles of implanted ions were measured using Rutherford backscattering spectroscopy and calculated by a code called TRIDYN. The structures of the implanted steel were observed by X-ray photoelectron spectroscopy and grazing-angle X-ray diffraction, respectively. It was found that the conventional heat-treated H13 steel could not be further hardened by the subsequent implanted C ions, and the thickness of the implanted layer was not an important factor for the Mo and C ion implantation to improve the wear resistance of the H13 steel. Mo ion implantation could obviously improve the wear resistance of the steel at an extraction voltage of 48 kV and a dose of 5 × 1017 cm -2 due to formation of a modification layer of little oxidation with Mo 2 C in the implanted surface.

Changes of Structural-Phase Condition in 18CrNi3MoA-SH Steel After Elektrolyte-Plasma Processing

2012 ◽  
Vol 601 ◽  
pp. 74-78 ◽  
Author(s):  
Mazhyn Skakov ◽  
Lyaila Bayatanova ◽  
Michael Sheffler
Keyword(s):  
Wear Resistance ◽  
Plasma Treatment ◽  
Structural Phase ◽  
Plasma Processing ◽  
High Wear Resistance ◽  
Initial State ◽  
Drilling Tool ◽  
Steel Microstructure ◽  
Fine Grained ◽  
Bainite Structure

The research shows the results of electrolyte-plasma treatment influence on structure-phase state, mechanical properties and wear-resistance of drilling tool steel samples. The comparative analysis of microstructure, microhardness and wear-resistance of the samples in initial state and after electrolyte-plasma treatment is represented. It was found out that 18CrNi3MoA-Sh steel microstructure has fine-grained martensite-bainite structure after the treatment. It was determined that 18CrNi3MoA-Sh steel possesses high wear-resistance after electrolyte-plasma treatment, so that technology is characterized by low power consumption and cost price. The initial state microhardness is 2800 MPa on the average. Microhardness on the bearing lane surface after electrolyte-plasma processing is 7500 MPa on the average. Microhardness increases in 2-2.5 times more before treatment that indicates the technology efficiency.

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