Numerical study of tube cathode arc with anode melting

Abstract

Tungsten Inert Gas (TIG) arc is the most widely employed type of a plasma torch and enables to produce arc plasma with high energy density. Therefore it is suitable as a heat source especially for processes to require concentrating the heat input at a point. On the other hand, Tube Cathode Arc (TCA) to be a kind of TIG produces the arc plasma by introducing inner shielding gas through the central hole of the tube cathode. In this paper, as the basic heat source property of argon (Ar) TCA, the property of the arc plasma and the heat input intensity onto a water-cooled copper anode for various inner shielding gas flow rates were numerically analyzed. Furthermore, by employing stainless steel SUS304 anode, the geometry of it's weld penetration was also predicted. The results were compared with those for the conventional TIG. As a result, it was found that since TCA enables to heat the target material uniformly by controlling the inner shielding gas flow rate and preserve it from damage due to excessive heat input during the process, it is suitable for processes such as brazing, buildup or thermal spraying. © 2007 Springer-Verlag Berlin Heidelberg.