Aerodynamic behavior within the arc gap during arc spraying
- Shenyang Polytechnic Univ. (China)
Measurements indicated that the presence of electrodes in the atomizing gas stream reduces the gas pressure within the arc gap. A subatmospheric pressure is created within the wire tip envelope. This aerodynamic effect contributes to the stabilization of the spray arc. The amplitude of the reduction depends on the arc length and atomizing nozzle structure. The shorter the arc length, the larger the pressure reduction. The closed nozzle creates higher pressure reduction than that of the open nozzle. The highest pressure reduction appeared at the upstream inner portion of the electrode tips. A turbulent backlash gas flow close to the electrode tip surface is existing. This gas flow creates mixing effect of the thin molten film melted by the electric arc on the electrode tip surfaces. Since the arc length is governed by the arc voltage, the arc voltage has influence on this mixing effect. The effect has significance when composite and cored wires are arc sprayed.
- OSTI ID:
- 160474
- Report Number(s):
- CONF-940684--; ISBN 0-87170-509-5
- Country of Publication:
- United States
- Language:
- English
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