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2018 №12 (09) DOI of Article
10.15407/as2018.12.10
2018 №12 (11)


Avtomaticheskaya Svarka (Automatic Welding), #11-12, 2018, с. 103-117

Anode processes in welding arcs

I.V. Krivtsun


E.O. Paton Electric Welding Institute of the NAS of Ukraine. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine E-mail: office@paton.kiev.ua

The paper describes the approaches to theoretical investigation and mathematical models of physical processes running in the anode layer of high-current (~102 A) electric arcs, burning in inert gas at atmospheric pressure. Numerical studies of anode processes in electric arcs with nonevaporating (water-cooled) anode, as well as in welding arcs (arcs with evaporating anode) were performed. It is shown that anode potential drop in the considered arcs is negative, having an essentially nonuniform distribution in the region of anode attachment of the arc. The latter circumstance largely determines the pattern of electric current flowing and energy transfer between arc plasma and anode (arc contraction on the anode or discharge distributed over anode surface). A procedure of calculation of effective anode drop in electric arcs is proposed, allowing for the above change of anode potential drop along the anode surface. 32 Ref., 1 Tabl., 15 Fig.
Keywords: welding arc, arc plasma, anode layer, anode potential drop, heat flow into the anode, evaporation, mathematical modeling

Received: 10.09.2018
Published: 06.11.2018

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