Arc discharges operation in “elion” mode

Abstract This paper presents the results of a study of an electron-ion-plasma alitization system using two arc plasma generators: a gas plasma generator based on a non-self-sustained arc discharge with a thermionic cathode “PINK” and a gas-metal plasma generator based on an arc discharge with a cathode spot. The system for discharges supplying and biasing of the samples assumes two sub-modes of operation: the ion cleaning sub-mode (ion sub-mode) and the sub-mode of samples electron heating (electron sub-mode), thus realizing the “elion” mode of the system operation. During the experiments, both the dependences of the average values of currents and voltages of discharges burning and probe measurements of the instantaneous plasma parameters values in both system operating sub-modes were investigated. It is shown, that the electron sub-mode of system operation is characterized by an increased burning voltage, which is caused by the formation of a positive anode drop of more than 10 V in the plasmas. Such a potential distribution in the discharges ensures effective heating of the samples by the discharges plasmas electron component.

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COMPOSITE Cu-Cr MATERIALS UNDER THERMAL ACTION OF ELECTRIC ARC DISCHARGE PLASMA

10.46813/2021-131-098 ◽

2021 ◽

pp. 98-101

Author(s):

A. Murmantsev ◽

A. Veklich ◽

V. Boretskij ◽

M. Bartlová ◽

L. Dostál ◽

...

Keyword(s):

Discharge Plasma ◽

Arc Discharge ◽

Plasma Temperature ◽

Thermal Action ◽

Optical Emission ◽

Electric Arc ◽

Composite Electrodes ◽

Plasma Parameters ◽

Arc Discharges ◽

The Impact

The results of optical emission spectroscopy (OES) investigation of plasma of electric arc discharges in steadystate mode between Cu-Cr composite electrodes, manufactured at different sintered temperatures: 750, 850, 950 or 1050 °C, is presented. In particular, the impact of sintering temperature on erosion resistanceof such composite materials, which was determined in indirect manner by estimation of metal vapours content in the midsection of discharge gaps, is studied by the analysis of plasma parameters. These contents were calculated in assumption of local thermodynamic equilibrium (LTE) on the base of experimentally obtained radial distributions of plasma temperature and electron density.

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PLASMA-SURFACE INTERACTION OF ELECTRIC ARC DISCHARGE BETWEEN COMPOSITE Cu-Cr ELECTRODES

10.46813/2020-130-174 ◽

2020 ◽

pp. 174-178

Author(s):

A. Murmantsev ◽

A. Veklich ◽

V. Boretskij ◽

M. Bartlová ◽

L. Dostál ◽

...

Keyword(s):

Arc Discharge ◽

Optical Emission ◽

Electric Arc ◽

Surface Interaction ◽

Composite Electrodes ◽

Plasma Parameters ◽

Plasma Surface ◽

Air Atmosphere ◽

Different Temperatures ◽

Arc Discharges

In this work the plasma of electric arc discharges between Cu-Cr composite electrodes, which material were pressured and sintered at different temperatures 750 or 1050°С, are investigated by Optical Emission Spectroscopy (OES). The Scanning Electron Microscopy (SEM) with Energy-Dispersive X-ray Spectroscopy (EDXS) are used to study the working surface of electrodes, modified by thermal effect of breaking electrical arc in the air atmosphere. The erosion intensity of electrodes’ material due to plasma-surface interaction is estimated in indirect way by determination of metal vapours content in the discharge gap in an assumption of local thermodynamic equilibrium (LTE). The plasma composition is calculated in this case on the base of experimentally determined plasma parameters: temperature and electron density.

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MODERNIZATION FEATURES OF A VACUUM INSTALLATION BASED ON LOW-PRESSURE ARC DISCHARGE FOR COMPOSITE TIN-CU LAYERS FORMATION

Acta Polytechnica ◽

10.14311/ap.2015.55.0136 ◽

2015 ◽

Vol 55 (2) ◽

pp. 136-139 ◽

Cited By ~ 2

Author(s):

Dmitriy Tsyrenov ◽

Aleksandr Semenov ◽

Natalia Smirnyagina

Keyword(s):

Phase Composition ◽

Arc Discharge ◽

Plasma Generator ◽

Low Pressure ◽

Fused Silica ◽

Vacuum Arc ◽

Technological Parameters ◽

Layer Deposition ◽

Planar Magnetron ◽

Arc Discharges

A hybrid technology for forming composite TiN-Cu layers under the combined influence of a magnetron and low pressure arc discharges has been designed. The parameters of the plasma generator have been studied. The technological parameters for layer deposition in the conditions of coordinated action of the vacuum arc evaporator and the planar magnetron have been studied. This report describes the phase composition of TiN-Cu layers and the structure on fused silica substrates.

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Lowtemperature plasma generator for effective processing of materials

Ferrous Metallurgy Bulletin of Scientific Technical and Economic Information ◽

10.32339/0135-5910-2021-5-587-592 ◽

2021 ◽

Vol 77 (5) ◽

pp. 587-592

Author(s):

M. Kh. Gadzhiev ◽

A. S. Tyuftyaev ◽

Yu. M. Kulikov ◽

M. A. Sargsyan ◽

D. I. Yusupov ◽

...

Keyword(s):

Low Temperature ◽

Flow Rate ◽

Gas Flow ◽

Arc Discharge ◽

Plasma Jet ◽

Plasma Generator ◽

Low Temperature Plasma ◽

Temperature Plasma ◽

High Enthalpy ◽

High Resource

Low-temperature plasma is used in metallurgy for steel alloying by nitrogen, deoxidization of magnetic alloys, obtaining of steels with particularly low carbon content, metal cleaning of nonmetallic inclusions, desulfurization and other refining processes. The wide application of those technologies is restrained by absence of reliable generators of low-temperature plasma (GLP) with sufficient resource of continuous operation. As a result of studies, a universal generator of high-enthalpy plasma jet of various working gases was created. The generator has expanding channel of the output electrode with an efficiency of ~60 % for argon working gas and ~80% for nitrogen and air. It was shown that the developed generator of low-temperature plasma ensures formation of a weakly diverging (2α = 12°) plasma jet with a diameter D = 5–12 mm, an enthalpy of 5–50 kJ/g and a mass average temperature of 5–10 kK, at a full electric power of the arc discharge of 5–50 kW and a plasma-forming gas flow rate of 1–3 g/s. Results of the study of propane additions to the plasma-forming gas effect on the state of cathodes with inserts made of pure tungsten, lanthanum tungsten, and hafnium presented. It was shown that a small propane addition (1%) to the plasma-forming gas, results in reducing effect of the insert material. Study of the GLP operation at arc current 100A with addition to the working gas nitrogen maximum possible volume of propane, which don’t disturb stability of arc showed that for the developed plasma generator at the nitrogen flow rate ~0,45 g/s, the propane flow rate was ~0,33 g/s (not more than ~73 % of the plasma-forming gas). The created high-resource GLP with changeable electrodes enables to obtain at the exit a high-enthalpy plasma flow of various gases (argon, nitrogen, air) and can be a prototype of more powerful plasmotrons of various technological application, in particular for plasma metallurgy.

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Probe Measurements in a Negative Ion Plasma

Journal of the Physical Society of Japan ◽

10.1143/jpsj.67.158 ◽

1998 ◽

Vol 67 (1) ◽

pp. 158-162 ◽

Cited By ~ 11

Author(s):

Itsuo Ishikawa ◽

Satoru Iizuka ◽

Rikizo Hatakeyama ◽

Noriyoshi Sato

Keyword(s):

Negative Ion ◽

Ion Plasma ◽

Probe Measurements

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COMPARISON BETWEEN 2D TURBULENCE MODEL ESEL AND EXPERIMENTAL DATA FROM AUG AND COMPASS TOKAMAKS

Acta Polytechnica ◽

10.14311/ap.2015.55.0128 ◽

2015 ◽

Vol 55 (2) ◽

pp. 128-135 ◽

Cited By ~ 2

Author(s):

Peter Ondac ◽

Jan Horacek ◽

Jakub Seidl ◽

Petr Vondrácek ◽

Hans Werner Müller ◽

...

Keyword(s):

Turbulent Transport ◽

Plasma Potential ◽

Density Fluctuations ◽

Tokamak Plasma ◽

Plasma Parameters ◽

Fluid Turbulence ◽

Radial Profiles ◽

Parallel Dynamics ◽

Two Machines ◽

Probe Measurements

<p style="text-indent: 0px; margin: 0px;">In this article we have used the 2D fluid turbulence numerical model, ESEL, to simulate turbulent transport in edge tokamak plasma. Basic plasma parameters from the ASDEX Upgrade and COMPASS tokamaks are used as input for the model, and the output is compared with experimental observations obtained by reciprocating probe measurements from the two machines. Agreements were found in radial profiles of mean plasma potential and temperature, and in a level of density fluctuations. Disagreements, however, were found in the level of plasma potential and temperature fluctuations. This implicates a need for an extension of the ESEL model from 2D to 3D to fully resolve the parallel dynamics, and the coupling from the plasma to the sheath.</p>

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Magnetoacoustic Nonlinear Solitary and Freak Waves in Pair-Ion Plasma

Zeitschrift für Naturforschung A ◽

10.1515/zna-2019-0031 ◽

2019 ◽

Vol 74 (9) ◽

pp. 777-786 ◽

Cited By ~ 1

Author(s):

Papihra Sethi ◽

Kuldeep Singh ◽

N.S. Saini

Keyword(s):

Solitary Wave Solution ◽

Reductive Perturbation Method ◽

Number Density ◽

Kp Equation ◽

Temperature Ratio ◽

Plasma Parameters ◽

Freak Waves ◽

Positive Ions ◽

Ion Plasma ◽

Magnetohydrodynamic Model

AbstractAn investigation of magnetoacoustic nonlinear solitary and freak waves in a magnetised collisionless pair-ion plasma using two-dimensional magnetohydrodynamic model is presented. The reductive perturbation method is used to obtain the Kadomtsev–Petviashvili (KP) equation. The solitary wave solution of KP equation is examined. Further, on modulating KP equation, the nonlinear Schrödinger equation is derived with the help of appropriate transformation. The influence of various plasma parameters such as magnetic field strength, number density of ions, and temperature ratio of negative to positive ions, etc. on the propagation characteristics of solitary waves and first- as well as second-order magnetoacoustic freak waves in pair-ion plasma is examined.

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