scholarly journals Electron Beam Welding for Extremely High Vacuum Chamber.

Shinku ◽  
1991 ◽  
Vol 34 (6) ◽  
pp. 561-564
Author(s):  
Hiroshi KOMURO ◽  
Seiichi FURUTATE ◽  
Tsuneo ISHIGAKI ◽  
Katsujiro ITOH ◽  
Hajime ISHIMARU
Keyword(s):  
Electron Beam ◽  
Vacuum Chamber ◽  
Electron Beam Welding ◽  
High Vacuum ◽  
High Vacuum Chamber

scholarly journals Design of an Einzel Lens with Square Cross-Section

Electronics ◽  
2021 ◽  
Vol 10 (19) ◽  
pp. 2338
Author(s):  
Michał Krysztof
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
Cross Section ◽  
Vacuum Chamber ◽  
High Vacuum ◽  
Beam Current ◽  
Electron Beam Current ◽  
Beam Spot ◽  
High Vacuum Chamber ◽  
Beam Spot Diameter

In this paper, the results of modeling and simulation of a microcolumn are presented. The microcolumn is part of a developed miniature MEMS electron microscope equipped with a miniature MEMS high-vacuum micropump. Such an arrangement makes this device the first stand-alone miniature electron-optical device to operate without an external high-vacuum chamber. Before such a device can be fabricated, research on particular elements must be carried out to determine the working principles of the device. The results of the calculations described in this article help us to understand the work of a microcolumn with square holes in the electrodes. The formation of an electron beam spot at the anode is discussed. Further calculations and results show the dependence of the Einzel lens size on the electron beam spot diameter, electron beam current, and microcolumn focusing voltage. The results are used to define the optimal design of the developed MEMS electron microscope.

Development of fast heating electron beam annealing setup for ultra high vacuum chamber

2014 ◽  
Vol 85 (2) ◽  
pp. 025107 ◽  
Author(s):  
Sadhan Chandra Das ◽  
Abhijit Majumdar ◽  
Sumant Katiyal ◽  
T. Shripathi ◽  
R. Hippler
Keyword(s):  
Electron Beam ◽  
Vacuum Chamber ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Fast Heating ◽  
High Vacuum Chamber ◽  
Ultra High Vacuum Chamber

The Optimization Design of Vacuum Chamber in Vacuum Electron Beam Welding Machine

2012 ◽  
Vol 490-495 ◽  
pp. 1699-1703
Author(s):  
Wei Wei Yue ◽  
Yi Mei Song ◽  
Dong Bo Zhou ◽  
Cai Liao ◽  
Dan Ping Liu
Keyword(s):  
Computer Simulation ◽  
Electron Beam ◽  
Optimization Design ◽  
Vacuum Chamber ◽  
Electron Beam Welding ◽  
Simulation Software ◽  
Deformation Measurement ◽  
Improve Performance ◽  
Welding Machine

Chamber deformation in vacuum electron beam welding machine directly affects the processing precision of whole equipment.In order to further improve performance of the welding machine,by the use of the computer simulation software, the Chamber structure in some type of vacuum electron beam welding machine,was optimized designed. And the optimized results were verified in a actual vacuum chamber. The results of deformation measurement show that the vacuum chamber optimization design is successful.

Study Of Al Surface Segregation In Icosahedral A162Cu25.5Fe12.5

1998 ◽  
Vol 553 ◽  
Author(s):  
M. GIL-GAVATZ ◽  
D. Rouxel ◽  
P. Pigeat ◽  
B. Weber ◽  
J.-M. Dubois
Keyword(s):  
Surface Segregation ◽  
Vacuum Chamber ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Electron Spectrometer ◽  
Temperature Dependent ◽  
Self Diffusion ◽  
Different Temperatures ◽  
High Vacuum Chamber

AbstractSurface segregation of aluminium was observed during oxidation experiments of icosahedral A162Cu25.5 Fel12.5, performed in-situ and at different temperatures in the ultra-high vacuum chamber of a scanning Auger electron spectrometer. Two regimes, below and above 770K, were observed in relation with severe segregation of Al atoms at the surface for T > 770K. We postulate that this temperature dependent segregation rate is representative of the aluminium transport towards the surface of the quasicrystal. By analogy with classical diffusion experiments, we can thus determine reasonable estimates of the activation energy for Al self-diffusion in this quasicrystal. The results are consistent with the existence of phason flips below 770K and thermal vacancies above this temperature.

Welding-Brazing Characteristic in Electron Beam Joining Vanadium Alloy and Stainless Steel

2015 ◽  
Vol 1088 ◽  
pp. 130-134
Author(s):  
Ya Rong Wang ◽  
Yang Yu ◽  
Wei Chao Zhang
Keyword(s):  
Stainless Steel ◽  
Electron Beam ◽  
Electron Beam Welding ◽  
High Vacuum ◽  
Welding Process ◽  
Dissimilar Materials ◽  
Temperature Fields ◽  
Residual Tensile Stress ◽  
Stress Distributions ◽  
Vanadium Alloy

The high vacuum electron beam welding-brazing was used to joining vanadium alloy (V-5Cr-5Ti) with stainless–steel (HR-2). The temperature fields and stress distributions in the V-5Cr-5Ti/HR-2 joint during the welding process were numerically simulated and the effect of the electron beam off-set distance was studied. The results show that the accurate heat input and proper molten pool position can help to control the fusion ratio of the V/Fe. The electron beam should off set on the stainless steel side rather than vanadium alloy side, and the best range of the distances off-set is 0-0.5mm. The residual stress appears to be bimodal and asymmetric. The maximum lateral residual tensile stress reached 388MPa at the V-5Cr-5Ti side. The joints with the characters of welding and brazing and the metallurgically bonded joint was achieved with 0.3mm beam off-set. With the liquid-to-solid interalloying of dissimilar materials controlled well, a reaction zone is gained on the interface. The maximum tensile strength of vanadium alloy/stainless-steel dissimilar alloy jointswas up to 200MPa with no defect.

Toward Growing III-V Clusters with Metalorganic Precursors

1997 ◽  
Vol 468 ◽  
Author(s):  
A. Demchuk ◽  
J. Porter ◽  
B. Koplitz
Keyword(s):  
Excimer Laser ◽  
Vacuum Chamber ◽  
High Vacuum ◽  
Pulsed Laser ◽  
Quadrupole Mass ◽  
Reaction Region ◽  
High Vacuum Chamber ◽  
Arf Excimer Laser ◽  
193 Nm ◽  
Pulsed Nozzle

ABSTRACTThe present work reports on the formation of GaN-containing clusters from metalorganic precursors by combining pulsed laser photolysis and pulsed nozzle methods. Ammonia (NH3) and triethylgallium (C2H5)3Ga (TEG) or trimethylgallium (CH3)3Ga (TMG) with He, Ar, or N2 as the carrier gas are introduced into a high vacuum chamber via a specialized dual pulsed nozzle source. The light from an ArF excimer laser (193 nm, 23 ns FWHM) is focused into the mixing and reaction region of the nozzle source, and the products are then mass analyzed with a quadrupole mass spectrometer. Efficient laser-assisted growth of (GaN)x-containing clusters is shown with this technique.

scholarly journals Prevention of Reversed Flow in Gas Divertor with High Vacuum Chamber

2000 ◽  
Vol 37 (6) ◽  
pp. 555-556 ◽  
Author(s):  
Akihiro MATSUBARA ◽  
Ryoichiro MURATA ◽  
Ken NAGATA ◽  
Takehisa SHIBUYA ◽  
Akira TONEGAWA ◽  
...  
Keyword(s):  
Vacuum Chamber ◽  
High Vacuum ◽  
Reversed Flow ◽  
High Vacuum Chamber

Low Temperature Laser-Assisted Gas Phase Reactivity of TMGa with NH3 and Oxygen-Containing Compounds (H2O, CH3OH, O(CH3)2) in Constrained Pulsed Expansions

2002 ◽  
Vol 743 ◽  
Author(s):  
Alexander Demchuk ◽  
Michael Lynch ◽  
Steven Simpson ◽  
Brent Koplitz
Keyword(s):  
Gas Phase ◽  
Vacuum Chamber ◽  
Cluster Formation ◽  
High Vacuum ◽  
Oxygen Species ◽  
Quadrupole Mass ◽  
High Vacuum Chamber ◽  
Arf Excimer Laser ◽  
Gas Nozzle ◽  
193 Nm

ABSTRACTThe present work reports on the study of III-V gas phase reactivity in constrained gas pulse expansions of trimethylgallium (TMGa) and oxygen derivative compounds (H2O, CH3OH, O(CH3)2) with and without ammonia. The precursors are introduced separately into a high vacuum chamber via a multipulsed gas nozzle assembly. The gas mixtures are then exposed to a UV pulse from an ArF excimer laser (λ=193 nm) and the products are mass analyzed with a quadrupole mass spectrometer. The efficient laser-assisted growth of Ga-O-containing clusters in the form of [(CH3)2GaOR] x, where R is H or CH3, has been revealed. Different behavior can be seen in the reaction of TMG and the oxygen species depending on the presence of H atoms bonded to the oxygen. Significant influence of NH3 on cluster formation and oxygen incorporation is demonstrated.

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