Numerical analysis of energy source properties of hollow cathode arc

Since a plasma torch can stabilize high temperature arc plasma by employing a shielding gas, it is widely utilized as a heat source. Gas Tungsten Arc (GTA) is the most widely employed type of the plasma torch. GTA enables to produce the arc plasma with high energy density. Therefore it is suitable especially for processes to require concentrating the heat input at a point but less effective for processes to require heating the target material uniformly. On the other hand, Hollow Cathode Arc (HCA) to be a kind of GTA produces the arc plasma by introducing the shielding gas from the tip of the cathode. It has been studied as a heat source especially in low pressure, for example, for space welding or plasma CVD. As an application at the atmospheric pressure, it can be utilized for processes such as thermal spraying. In this paper, the basic heat source properties of argon HCA at the atmospheric pressure are numerically analyzed. Furthermore, the properties are compared with those for the conventional GTA.