Measurements of the anode temperature in a vacuum arc with an asymmetric hot refractory Mo anode

Abstract As the main source of the vacuum arc plasma, cathode spots (CSs) play an important role on the behaviors of the vacuum arc. Their characteristics are affected by many factors, especially by the magnetic field. In this paper, the characteristics of the plasma jet from a single CS in vacuum arc under external axial magnetic field (AMF) are studied. A multi-species magneto-hydro-dynamic (MHD) model is established to describe the vacuum arc. The anode temperature is calculated by the anode activity model based on the energy flux obtained from the MHD model. The simulation results indicate that the external AMF has a significant effect on the characteristic of the plasma jet. When the external AMF is high enough, a bright spot appears on the anode surface. This is because with a higher AMF, the contraction of the diffused arc becomes more obvious, leading to a higher energy flux to the anode and thus a higher anode temperature. Then more secondary plasma can be generated near the anode, and the brightness of the ‘anode spot’ increases. During this process, the arc appearance gradually changes from a cone to a dumbbell shape. The appearance of the plasma jet calculated in the model is consistent with the experimental results.

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Anode Temperature and Plasma Sheath Dynamics of High Current Vacuum Arc After Current Zero

IEEE Transactions on Plasma Science ◽

10.1109/tps.2013.2266920 ◽

2013 ◽

Vol 41 (8) ◽

pp. 2022-2028 ◽

Cited By ~ 11

Author(s):

Anton V. Schneider ◽

Sergey A. Popov ◽

Alexander V. Batrakov ◽

Gabriela Sandolache ◽

Hans Schellekens

Keyword(s):

Plasma Sheath ◽

Vacuum Arc ◽

High Current ◽

Anode Temperature ◽

Current Zero

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Copper film deposition and anode temperature measurements in a vacuum arc with tungsten anode

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2007.05.047 ◽

2007 ◽

Vol 202 (4-7) ◽

pp. 925-930 ◽

Cited By ~ 6

Author(s):

I.I. Beilis ◽

A. Shnaiderman ◽

A. Shashurin ◽

R.L. Boxman ◽

S. Goldsmith

Keyword(s):

Copper Film ◽

Film Deposition ◽

Temperature Measurements ◽

Vacuum Arc ◽

Anode Temperature ◽

Tungsten Anode

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Preparation and characterization of thin films of carbon nitride

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100136891 ◽

1995 ◽

Vol 53 ◽

pp. 104-105

Author(s):

L. Wan ◽

R. F. Egerton

Keyword(s):

Carbon Nitride ◽

Arc Discharge ◽

Ion Beam ◽

Chemical Vapor ◽

Reactive Sputtering ◽

Vacuum Arc ◽

Specimen Preparation ◽

Bonding Structure ◽

Electron Energy Loss

INTRODUCTION Recently, a new compound carbon nitride (CNx) has captured the attention of materials scientists, resulting from the prediction of a metastable crystal structure β-C3N4. Calculations showed that the mechanical properties of β-C3N4 are close to those of diamond. Various methods, including high pressure synthesis, ion beam deposition, chemical vapor deposition, plasma enhanced evaporation, and reactive sputtering, have been used in an attempt to make this compound. In this paper, we present the results of electron energy loss spectroscopy (EELS) analysis of composition and bonding structure of CNX films deposited by two different methods.SPECIMEN PREPARATION Specimens were prepared by arc-discharge evaporation and reactive sputtering. The apparatus for evaporation is similar to the traditional setup of vacuum arc-discharge evaporation, but working in a 0.05 torr ambient of nitrogen or ammonia. A bias was applied between the carbon source and the substrate in order to generate more ions and electrons and change their energy. During deposition, this bias causes a secondary discharge between the source and the substrate.

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