scholarly journals Combined Processing of Micro Cutters Using a Beam of Fast Argon Atoms in Plasma

Coatings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 465
Author(s):  
Alexander Metel ◽  
Yury Melnik ◽  
Enver Mustafaev ◽  
Ilya Minin ◽  
Petr Pivkin
Keyword(s):  
Space Charge ◽  
Charge Exchange ◽  
High Voltage ◽  
Discharge Plasma ◽  
Focal Point ◽  
New Method ◽  
Initial Radius ◽  
Coating Deposition ◽  
Gas Discharge Plasma ◽  
Pass Through

We present a new method for coating deposition on micro cutters without an increase in their cutting edges radii caused by the deposition. For this purpose, the cutting edges are sharpened before the coating deposition with a concentrated beam of fast argon atoms. The sharpening decreases the initial radius and, hence, limits its value after the coating deposition. The concentrated beam of fast argon atoms is generated using an immersed in the gas discharge plasma concave grid under a negative high voltage. Ions accelerated from the plasma by the grid pass through the grid holes and are concentrated in the focal point of the grid. As a result of the charge exchange in the space charge sheaths of the grid, they are transformed into fast atoms. A uniform sputtering by the fast atoms of the micro-cutter surface reduces the radius of its cutting edge.

New Method for Synthesis of Hard Coatings Using Pulsed Bombardment with High-Energy Gas Atoms

2016 ◽  
Vol 876 ◽  
pp. 14-24
Author(s):  
Abdumalik Rakhimovich Seitkulov ◽  
Sergey Nikolaevich Grigoriev ◽  
Alexander Sergeevich Metel ◽  
Marina Aleksandrovna Volosova ◽  
Yury Andreevich Melnik
Keyword(s):  
Surface Layer ◽  
Space Charge ◽  
Charge Exchange ◽  
High Voltage ◽  
Discharge Plasma ◽  
High Energy ◽  
Hard Coatings ◽  
Magnetron Discharge ◽  
Metal Atoms ◽  
Pass Through

For deposition of hard coatings is used a source of metal atoms accompanied by high-energy gas atoms. The metal atoms are produced due to sputtering a flat rectangular target in low pressure magnetron discharge. The gas atoms with energy up to 30 keV are produced due to charge exchange collisions of accelerated ions in space charge sheaths near the surfaces of a grid parallel to the target. The ions are extracted from the discharge plasma and accelerated by high-voltage pulses applied to the grid. The metal atoms pass through the grid and deposit on the products. Conjunction of their trajectories with those of gas atoms bombarding the growing coating allows synthesis of the coatings on rotating dielectric products. Mixing by high-energy gas atoms of the coating atoms and atoms of the product material in its surface layer improves the coating adhesion.

scholarly journals REDISTRIBUTION OF SPUTTERED MATERIAL IN A PLANE IONPLASMA SYSTEM WITH AN ABNORMAL GLOW DISCHARGE

2020 ◽  
pp. 103-106
Author(s):  
A.I. Kuzmichev ◽  
M.S. Melnichenko ◽  
V.G. Shinkarenko ◽  
V.M. Shulaev
Keyword(s):  
Glow Discharge ◽  
Space Charge ◽  
Charge Exchange ◽  
Electrode System ◽  
Material Flows ◽  
Coating Deposition ◽  
Charge Layer ◽  
Plane Parallel ◽  
Gas Molecules ◽  
Parallel Electrode

The redistribution of the flow of sputtered material of a target (cathode) between the collector and the target in a plane-parallel electrode system with an anomalous glow discharge is analyzed in the kinetic approximation. Sputtering is the result of bombardment of the target by gas ions accelerated in the near-cathode space charge layer and by fast neutral atoms formed as a result of resonant ion charge exchange. Sputtered atoms partially return to the target due to collisions with gas molecules. The formulas were obtained, which were confirmed in the experiment that makes it possible to correctly estimate the ratio of the sputtered material flows deposited on the collector and the target. The results of the work are used to calculate the parameters of the processes of coating deposition and ion cleaning of the target under conditions of the anomalous glow discharge.

scholarly journals Influence of heat flows in a gas discharge plasma on its electric properties

2021 ◽  
Author(s):  
A.S. Bankovsky ◽  
◽  
A.A. Zaharov ◽  
A.A. Potapov ◽  
A.A. Potapov ◽  
...  
Keyword(s):  
Heat Flux ◽  
Electric Field ◽  
Space Charge ◽  
Discharge Plasma ◽  
Gas Discharge ◽  
Heat Fluxes ◽  
Longitudinal Electric Field ◽  
Practical Significance ◽  
Gas Discharge Plasma ◽  
Kinetic Coefficients

The heat flux and the associated space charge in a gas-discharge plasma can lead to a change in the properties of the corresponding electronic devices: a change in the kinetic coefficients and the temporal instability of their parameters. In devices with small transverse dimensions, the surface charge field, which significantly affects the space charge in the plasma, can also affect the current in the quasineutral plasma, changing the magnitude of the electric field component, which depends on the heat fluxes of the plasma. Knowledge of the analytical dependences of the component of the longitudinal electric field that provides the discharge current on the parameters of the plasma, the heat flux of electrons and its geometry makes it possible to estimate in detail the parameters of real plasma devices. Purpose. Obtain and analyze analytical expressions for the longitudinal electric field in a confined plasma in the ambipolar diffusion mode, taking into account the heat fluxes of electrons, the value of which depends on the frequency of collisions of electrons with atoms when approximated as a power-law velocity function. Results. The equations of electron balance are obtained in integral form for a bounded flat plasma with allowance for the heat flux of electrons. Practical significance. The calculation results make it possible to evaluate the effect of the heat flux of electrons of a low-temperature flat plasma with light and heavy ions on their electrical properties.

scholarly journals Surface Quality of Metal Parts Produced by Laser Powder Bed Fusion: Ion Polishing in Gas-Discharge Plasma Proposal

Technologies ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 27
Author(s):  
Alexander S. Metel ◽  
Sergey N. Grigoriev ◽  
Tatiana V. Tarasova ◽  
Yury A. Melnik ◽  
Marina A. Volosova ◽  
...  
Keyword(s):  
Additive Manufacturing ◽  
Discharge Plasma ◽  
Current Trend ◽  
Gas Discharge ◽  
Functional Coating ◽  
Powder Bed ◽  
Coating Deposition ◽  
Gas Discharge Plasma ◽  
Analytical Research ◽  
First Time

Additive manufacturing has evolved over the past decades into a technology that provides freedom of design through the ability to produce complex-shaped solid structures, reducing the operational time and material volumes in manufacturing significantly. However, the surface of parts manufactured by the additive method remains now extremely rough. The current trend of expanding the industrial application of additive manufacturing is researching surface roughness and finishing. Moreover, the limited choice of materials suitable for additive manufacturing does not satisfy the diverse design requirements, necessitating additional coatings deposition. Requirements for surface treatment and coating deposition technology depend on the intended use of the parts, their material, and technology. In most cases, they cannot be determined based on existing knowledge and experience. It determines the scientific relevance of the analytical research and development of scientific and technological principles of finishing parts obtained by laser additive manufacturing and functional coating deposition. There is a scientific novelty of analytical research that proposes gas-discharge plasma processing for finishing laser additive manufactured parts and technological principles development including three processing stages—explosive ablation, polishing with a concentrated beam of fast neutral argon atoms, and coating deposition—for the first time.

A New High Intensity Grid Cap for RCA-EMU-3 Electron Microscopes

1968 ◽  
Vol 26 ◽  
pp. 316-317
Author(s):  
George Christov ◽  
Bolivar J. Lloyd
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
High Voltage ◽  
High Intensity ◽  
Electron Gun ◽  
Tungsten Filament ◽  
Fluorescent Screen ◽  
Electron Microscopes ◽  
Pass Through ◽  
Ground Potential

A new high intensity grid cap has been designed for the RCA-EMU-3 electron microscope. Various parameters of the new grid cap were investigated to determine its characteristics. The increase in illumination produced provides ease of focusing on the fluorescent screen at magnifications from 1500 to 50,000 times using an accelerating voltage of 50 KV.The EMU-3 type electron gun assembly consists of a V-shaped tungsten filament for a cathode with a thin metal threaded cathode shield and an anode with a central aperture to permit the beam to course the length of the column. The cathode shield is negatively biased at a potential of several hundred volts with respect to the filament. The electron beam is formed by electrons emitted from the tip of the filament which pass through an aperture of 0.1 inch diameter in the cap and then it is accelerated by the negative high voltage through a 0.625 inch diameter aperture in the anode which is at ground potential.

Photoelectrical Properties of Semiconductor in Contact with Gas Discharge Plasma

1997 ◽  
Vol 7 (5) ◽  
pp. 1039-1044
Author(s):  
N. N. Lebedeva ◽  
V. I. Orbukh ◽  
B. G. Salamov ◽  
M. Özer ◽  
K. Çolakoǧlu ◽  
...  
Keyword(s):  
Discharge Plasma ◽  
Gas Discharge ◽  
Gas Discharge Plasma ◽  
Photoelectrical Properties
Sign in / Sign up

Export Citation Format

Share Document