Investigation of forming of electron beam in glow discharge electron guns with additional electrode

The algorithm is considered for calculating the focal distance of a hollow conical electron beam generated by high-voltage glow discharge electron guns with magnetic focusing of the beam in the drift region, as well as a method for calculating the diameter of the focal ring and its thickness for such a beam. The proposed algorithm is based on the theory of electron drift in the field of a focusing magnetic lens and is designed using the methods of discrete mathematics and the minimax analysis. The obtained simulation results made it possible to establish the influence of the magnetic lens current on the focal diameter of a hollow conical electron beam and on its focal ring thickness. It is shown that the change in the focal parameters of a hollow conical electron beam can be effectively provided through the regulation of the magnetic lens current.

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Analytical and numerical methods for calculation the deep of penetration the welding seam formed by the electron beam generated by glow discarge electron guns

Information and communication technologies, electronic engineering ◽

10.23939/ictee2021.01.112 ◽

2021 ◽

Vol 1 (1) ◽

pp. 112-119

Author(s):

I. Melnyk ◽

◽

S. Tuhai ◽

V. Kyryk ◽

D. Kovalchuk ◽

...

Keyword(s):

Electron Beam ◽

Glow Discharge ◽

Discharge Chamber ◽

Welding Process ◽

The Novel ◽

Welding Seam ◽

Non Linear Equation ◽

Electron Guns ◽

Welding Joints

The article is devoted to the problem of defining the focal diameter of electron beam, formed by the glow discharge electron guns, as well as the necessary pressure in the gun chamber for realising the welding process. Taking into account, that glow discharge electron guns are widely used in industry for welding of different metals, and that for providing the high quality of welding joints estimation of energetic parameters in beam focus is very important, proposed methods are very important for effective elaboration and designing of the novel glow discharge electron guns constructions for specific technological operations. With known focal beam deameter and thermodinamic parameters of welding details material the deep of penetration of welding seam, as well as the necessary pressure in discharge chamber have been estimatied. Two proposed methods are generally based on the analytical solving of explite equation and on numeracal solving of sophisticated non-linear equation. Obtained simulation results with and without taking into account the spsace charge of own beam electrons are also given

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Simplyfied Universal Analytical Model for Defining of Plasma Boundary Position in the Glow Discharge Electron Guns for Forming Conic Hollow Electron Beam

2019 IEEE 39th International Conference on Electronics and Nanotechnology (ELNANO) ◽

10.1109/elnano.2019.8783454 ◽

2019 ◽

Author(s):

I.V. Melnyk ◽

V.G. Melnyk ◽

B.A. Tugai ◽

S.B. Tuhai ◽

N.I. Mieshkova ◽

...

Keyword(s):

Electron Beam ◽

Glow Discharge ◽

Analytical Model ◽

Plasma Boundary ◽

Boundary Position ◽

Electron Guns ◽

Hollow Electron Beam

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A controller for safe, convenient operation of LaB6 emitters on electron-beam instruments

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075798 ◽

1983 ◽

Vol 41 ◽

pp. 408-409

Author(s):

W. J. Abramson ◽

H. W. Estry ◽

L. F. Allard

Keyword(s):

Electron Beam ◽

Control System ◽

Thermal Shock ◽

Appropriate Care ◽

Electron Guns ◽

Tungsten Filaments ◽

Order Of Magnitude ◽

Main Components

LaB6 emitters are becoming increasingly popular as direct replacements for tungsten filaments in the electron guns of modern electron-beam instruments. These emitters offer order of magnitude increases in beam brightness, and, with appropriate care in operation, a corresponding increase in source lifetime. They are, however, an order of magnitude more expensive, and may be easily damaged (by improper vacuum conditions and thermal shock) during saturation/desaturation operations. These operations typically require several minutes of an operator's attention, which becomes tedious and subject to error, particularly since the emitter must be cooled during sample exchanges to minimize damage from random vacuum excursions. We have designed a control system for LaBg emitters which relieves the operator of the necessity for manually controlling the emitter power, minimizes the danger of accidental improper operation, and makes the use of these emitters routine on multi-user instruments.Figure 1 is a block schematic of the main components of the control system, and Figure 2 shows the control box.

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