ABSTRACT
Arc discharge is a kind of direct current (DC) discharge that is characterized by low voltage and high current, which is generated by a pointed small wire (cathode) and surrounding metal surface (anode) [1-7]. The cathode and the anode are contained in a small nozzle (arc generator). The luminous gas phase created in the gap between the cathode and the anode is blown out of the arc generator by the flow of the carrier gas, which forms a jet of the luminous gas. The pressure of the carrier gas is generally superatmospheric at the entrance of the arc generator. When the luminous gas is blown into atmospheric pressure, the temperature of the flame is very hot, and the high-pressure arc torch is used as a heat source for cutting metals and welding processes. Cascade arc is the arc that is created by a special mode of arc generation, in which the cathode and the anode are separated by a series of conducting walls that are separated each other by insulators.
