Discharge and metallic plasma generation characteristics of an insulated anode with a micropore

Abstract

An insulated-anode electrode structure with a micropore (IAESM) is proposed in this paper. The aim of this study is to examine the effect that the micropore structure has on the discharge characteristics and plasma generation characteristics of the electrode in pulsed vacuum discharge. In this study, currents flowing through the cathode and the anode of the discharge electrode are simultaneously measured by two identical Rogowski coils, and plasma density and the plasma propagation speed are measured by using an improved Langmuir probe method. First, the differences in discharge characteristics and plasma generation characteristics among the IAESM and two known electrode structures, the non-insulated-anode electrode structure (NIAES) and the insulated-anode electrode structure (IAES), were compared and analyzed. Then, based on the IAESM, the effect of the micropore size on discharge characteristics and plasma generation characteristics is discussed. The results show that the IAESM discharge current flowed through the cathode with the same amplitude as in the NIAES, and the peak plasma density and the plasma propagation speed were significantly larger. The data obtained from Langmuir probes indicate that when the cross-sectional area of the micropore was reduced from 0.60 mm2 to 0.04 mm2, the peak plasma density and the plasma propagation speed are increased by 2.30 times and 2.56 times, respectively.