| 2005 №04 (01) | 2005 №04 (03) |
The Paton Welding Journal, 2005, #4, 7-13 pages
Peculiarities of the microplasma powder cladding process
P.P. Kalina, A.V. Yarovitsyn, K.A. Yushchenko
E.O. Paton Electric Welding Institute of the NASU. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.Abstract
Thermal power of the arc, effective efficiency of heating of a workpiece, powder utilisation factor, geometrical parameters of the weld and coefficient of heat flow concentration in microplasma powder cladding were studied. The current and, to a lesser degree, powder consumption were found to be the main technological parameters affecting thermal characteristics of the arc. The coefficient of concentration of heat flow of the plasma arc in microplasma powder cladding is determined primarily by the diameter of the plasmatron nozzle channels, arc length and addition of powder to the arc.
Keywords: microplasma powder cladding, calorimetry, effective thermal power, effective efficiency of heating of workpiece, heat losses at plasmatron nozzles, heat balance, powder utilisation factor, geometrical parameters of cladding, coefficient of heat flow concentration
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