• Title, Summary, Keyword: Electron Beam

Search Result 2,120, Processing Time 0.055 seconds

Characteristics of Electron Beam Extraction in Large Area Electron Beam Generator

  • Woo, Sung-Hun;Lee, Hong-Sik
    • KIEE International Transactions on Electrophysics and Applications
    • /
    • v.4C no.1
    • /
    • pp.10-14
    • /
    • 2004
  • A large area electron beam generator has been developed for industrial applications, for example, waste water cleaning, flue gas treatment, and food pasteurization. The operational principle is based on the emission of secondary electrons from the cathode when ions in the plasma contact the cathode, which are accelerated toward the exit window by the gradient of the electric potential. Conventional electron beam generators require an electron beam scanning mechanism because a small area thermal electron emitter is used. The electron beam of the large area electron beam generator does not need to be scanned over target material because the beam area is considerable. We have fabricated a large area electron beam generator with peak energy of 200keV, and a beam diameter of 200mm. The electron beam current has been investigated as a function of accelerating voltage and distance from the extracting window while its radial distribution in front of the extracting window has been also measured.

Creation of Electron Beam Probe in Scanning Electron Microscopy (주사 전자 현미경에서 전자빔 프르브 생성)

  • Lim, Sun-Jong;Lee, Chan-Hong
    • Transactions of the Korean Society of Machine Tool Engineers
    • /
    • v.17 no.5
    • /
    • pp.52-57
    • /
    • 2008
  • Most of the electrons emitted from the filament, are captured by the anode. The portion of the electron current that leaves the gun through the hole in the anode is called the beam current. Electron beam probe is called the focused beam on the specimen. Because of the lenes and aperture, the probe current becomes smaller than the beam current. It generate various signals(backscattered electron, secondary electron) in an interaction with the specimen atoms. Backscattered electron provide an useful signal for composition and local specimen surface inclination. Secondary electron is used far the formation of surface imagination. The steady electron beam probe is very important for the imagination formation and the brightness. In this paper, we show the results of developed elements that create electron beam probe and the measured beam probe in various acceleration voltages by Faraday cup. These data are used to analysis and improve the performance of the system in the development.

Effects of Beam Quality in a Free-Electron Laser Oscillator with Two Electron Beams

  • Nam, Soon-Kwon
    • Journal of the Korean Physical Society
    • /
    • v.71 no.9
    • /
    • pp.548-553
    • /
    • 2017
  • We have studied the electron beam quality in a free-electron laser (FEL) oscillator by using two electron beams of different harmonically related energies in the FEL facility, which is operated in the infrared and far-infrared regions. The electron beam quality, such as emittance, energy spread, and higher-order modes were studied using an extended three-dimensional (3D) FEL code for two electron beams that we have developed. The variations in the radiation amplitude of the electron beam's emittances, and energy spread were also calculated for a tapered wiggler for the multi-particle and multi-pass number using a new 3D code. The evolution of the radiation field intensity for higher-order modes of the wiggler with beam emittance and energy spread was studied for the two-electron beam's FEL performance. We found that the radiation intensity was degraded due to the energy spread and the emittance of the electron beam. We minimized the degradation of the radiation intensity by optimizing the tapered wiggler for the coupled two-beam FEL oscillator.

Establishment of Gun Head Unit for Electron Beam Machining System (전자빔건 헤드유니트의 설계와 제작)

  • Kang J.H.;Lee C.H.;Choi J.H.
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • /
    • pp.1875-1878
    • /
    • 2005
  • It is not efficient and scarcely out of the question to use commercial expensive electron beam lithography system widely used for semiconductor fabrication process for the manufacturing application field of various devices in the small business scope. Then scanning electron microscope based electron beam machining system is maybe regarded as a powerful model can be used for it simply. To get a complete suite of thus proper system, column unit build up with electron beam gun head unit is necessarily required more than anything else to modify scanning electron microscope. In this study, various components included ceramic isolation plate and main body which are essentially constructed for electron beam gun head unit are designed and manufactured. And this electron beam gun head unit will be used for next connected study in the development step of scanning electron microscope based electron beam machining system.

  • PDF

냉음극을 이용한 plasma전자 beam의 전기적 입력특성 II

  • 전춘생;김상현;이보호
    • 전기의세계
    • /
    • v.27 no.6
    • /
    • pp.49-53
    • /
    • 1978
  • This paper investigates on the electric input characterisitcs of plasma electron beam in H$_{2}$ gas chamber with various pressures, effected by the shape and dimension of hollow screen cathode during electron beam is formed. The result are as follows: (1)Electron beam is formed in the region of positive resistance on the characteristic curve which shows the relation between the voltage and current of electron beam, independent of the shape and dimension of hollow screen cathode. (2)At a given electron beam current, electron beam voltage increases with the decreases of hollow screen cathode length and screen mesh number of it. (3)At a given electron beam current, electron beam voltage increases with the diameters of hollow screen cathode and electron beam hole of it.

  • PDF

Characteristics of Electron Beam Extraction in Cold Cathode Type Large Cross-Sectional Pulsed Electron Beam Generator (냉음극형 대면적 펄스 전자빔 가속기의 빔인출 특성)

  • Woo, S.H.;Lee, K.S.;Lee, D.I.;Lee, H.S.
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.1609-1611
    • /
    • 2001
  • A large cross-section pulsed electron beam generator of cold cathode type has been developed for industrial applications, for example, waste water cleaning, flue gas cleaning, and pasteurization etc. The operational principle is based on the emission of secondary electrons from cold cathode when ions in the plasma hit the cathode, which are accelerated toward exit window by the gradient of an electric potential. The conventional electron beam generators need an electron scanning beam because the small cross section thermal electron emitter is used. The electron beam of large cross-section pulsed electron beam generator do not need to be scanned over target material because the beam cross section is large by 300$cm^2$. We have fabricated the large cross-sectional pulsed electron beam generator with the peak energy of 200keV and beam diameter of 200mm and obtained the large area electron beam in the air. The electron beam current has been investigated as a function of accelerating voltage, glow discharge current, helium pressure, distance from the exit window and radial distribution in front of the exit window.

  • PDF

A Study on the Electrom Beam Weldability of 9%Ni Steel (I) - Penetration and Electron Beam Characteristics - (9%Ni 강의 전자빔 용접성에 관한 연구 (I) - 전자빔 특성과 용입 -)

  • 김숙환;강정윤
    • Journal of Welding and Joining
    • /
    • v.15 no.3
    • /
    • pp.79-87
    • /
    • 1997
  • This study was performed to evaluate basic characteristics of electron beam welding process for a 9% Ni steel plate. The principal welding process parameters, such as working distance, accelerating voltage, beam current and welding speed were investigated. The AB (Arata Beam) test method was also applied to characterize beam size and energy density of the electron beam welding process. The electron beam size was found to decrease with the increase of accelerating voltage and the decrease of working distance. So, in case of high voltage (150kV), spot size and energy density of electron beam were revealed to be 0.9mm and $6.5\times10^5W/\textrm{cm}^2$ respectively. The accelerating voltage among the welding parameters was found to be the most important factor governing the penetration depth. When the accelerating voltage of electron beam was low ($\leq$90kV), beam current and welding speed did not affect on the penetration depth significantly. However, in case of high voltage ($\geq$120kV), the depth of penetration increased very sensitively with the increase of beam current and the decrease of welding speed.

  • PDF

Electron Beam -Induced Graft Polymerization of Acrylic Aicd on Polypropylene Nonwoven Fabrics(I) (전자빔 가속기를 이용한 폴리프로필렌 섬유의 개질(I) - 전자빔 조사에 따른 폴리프로필렌 섬유의 물리적, 열적 특성변화 -)

  • ;N.I. Shtanko
    • Textile Coloration and Finishing
    • /
    • v.15 no.2
    • /
    • pp.102-108
    • /
    • 2003
  • Before studying graft polymerization of PP(polypropylene) nonwoven fabrics by electron beam preirradiation method, mechanical properties, thermal properties and degree of crystallinity of original and electron beam irradiated PP nonwoven fabrics were investigated. Morphological surface changes of electron beam irradiated PP nonwoven fabrics were not observed. And the melting temperature and crystallinity of electron beam irradiated PP nonwoven fabrics also did not change as compared with untreated PP nonwoven fabrics. But the breaking strength of electron beam irradiated PP nonwoven fabrics decreased with increasing electron beam absorbed dose due to breakdown of some parts of polymer main chain.

Electron beam 용접전원 system의 제어기술

  • 고상근;정기형;김상호
    • Journal of Welding and Joining
    • /
    • v.14 no.3
    • /
    • pp.29-40
    • /
    • 1996
  • Electron beam 용접은 전자총에서 발생된 electron beam을 렌즈로 집속시켜 고 에너지의 열원을 얻는 것을 기본 원리로 하고 있다. Electron beam은 렌즈에 의해 매우 작게 집속(0.1 - 1mm.PHI.)시켜 높은 에너지밀도로 만들 수 있으므로 용접을 매우 깊게(수십 - 수백 mm) 할 수 있다. 이러한 용접 특성은 모재의 열변형을 최소로 하여 용접 부위가 원래의 성질을 잃어버리는 것을 최소화한다. 그러나, deep welding 의 경우 입력 파워 밀도가 너무 큰 관계로 계면 부위가 기계적 충격에 약하다는 단점 을 갖고 있다. Electron beam 용접은 서로 다른 금속을 filler material 없이 용접할 수 있으며 복잡한 구조의 용접이 가능하다. 또한 대부분의 electron beam 용접은 진공 중에서 이루어지기 때문에 공기의 영향을 받지 않는다는(산화 방식) 특성을 갖고 있다. 즉, 공기와의 접촉이 적기 때문에 산화가 방지되고 용접 순도가 매우 높다는 장점을 갖고 있다. 이는 반면 장치가 거대해지고 비싸다는 단점으로 작용한다. 1980년대 부터 이러한 단점의 극복을 위해서 대기중에서의 electron beam 용접에 관한 연구가 수행 되어 실용화 단계에 이루고 있다. 최근 전자, computer기술의 발달로 electron beam 출력을 더욱 더 정밀하게 조절할 수 있고, computer와 sensor의 결합으로 자동용접 위치 제어와 NC(Numerical Control) 작업대의 설치로 완전 자동화 용접 공정이 가능 하다. 그 결과 높은 용접 속도를 얻을 수 있으며 무인 생산 체계에로의 응용이 가능 하다.

  • PDF

Tensile, Dynamic Mechanical, and Abrasion Properties of Glass Fiber Reinforced Diepoxidized Polycardanol Composites Cured by Electron Beam (전자빔에 의해 경화된 유리섬유/Diepoxidized Polycardanol 복합재료의 인장, 동역학 및 마모 특성)

  • Cheon, Jinsil;Cho, Donghwan
    • Textile Science and Engineering
    • /
    • v.53 no.3
    • /
    • pp.213-219
    • /
    • 2016
  • In the present study, the effect of electron beam irradiation on the tensile, dynamic mechanical, and abrasion properties of glass-fiber-reinforced diepoxidized polycardanol (DEPC) composites was explored. Triarylsulfonium hexafluoroantimonate, an antimonate-type photoinitiator (2 wt%) was added to diepoxidized cardanol (DEC) prior to composite curing by electron beam. The glass fabrics pre-impregnated with DEPC were consolidated by direct irradiation of electron beam at 400, 500, and 600 kGy at ambient temperature and pressure. The composite properties strongly depend on the applied electron beam intensity. The result indicates that electron beam curing of glass fiber/DEPC composites at 600 kGy resulted in the highest tensile modulus, tensile strength, dynamic storage modulus, abrasion resistance, and lowest damping among the applied electron beam absorption doses.