Experimental Study of Anode Activities in High Current Vacuum Arc Subjected to Axial Magnetic Fields Under Different Conditions

In this paper, high current vacuum arc (HCVA) characteristics and anode melting pool (AMP) flow phenomena under different conditions are researched and analyzed. Particularly, rotation phenomena of AMP are observed and analyzed. First, the influence of different arc currents on arc column and anode activities is researched. Experimental results show that the rotation phenomena of AMP become more significant when arc currents are very high. Then, the influence of electrode configurations on the AMP rotation is investigated. For larger h/D value electrode, vacuum arc can become more unstable and uncontrollable, the rotation of anode melting region cannot be found; for smaller h/D, the vacuum arc is more stable and the vacuum arc is controlled effectively by the axial magnetic field (AMF), also significant rotation of AMP has been found. For a smaller anode electrode, anode melting and rotation of AMP is more serious, which is due to the same energy inputs smaller electrode. Finally, the influence of pure Cu and CuCr30 electrode on anode melting and flow is compared and analyzed. Experimental results show that AMP rotation with pure Cu material is more significant than that with CuCr30 material for the same arc current interruption. Liquid macroparticles' diameters with pure Cu electrode are significantly larger than that with CuCr30 materials.