Electrode erosion in high-current megavolt electric discharge in SF6 gas

In powerful pulsed installations used for investigations on controlled thermonuclear fusion high-current megavolt electric spark gaps with SF6 gas serving as a workng medium are used as commutators. The objective of the given study is to find erosion-resistant materials with low mass and volume carry-over out of the number of most frequently used for manufacturing electrodes for high-current megavolt SF6 gas commutators. The effect of the electrode erosion on stability of SF6 gas breakdown voltage at commutating currents of hundreds of kiloamperes is analyzed as well. On the basis of the obtained data it can be recommended to use tungsten-copper compositions, as well as steel-3 and stainless steel as materials for electrodes in the high-current megavolt SF6 gas commutators