Deuterium Retention in Graphite and its Removal by Inert Gas Glow Discharge

Abstract

The hydrogen isotope retention and its removal by inert gas glow discharge for graphite was investigated by residual gas analysis. The amount of retained hydrogen isotope in graphite during the deuterium glow discharge was about 1.0×10¹⁷ cm², which was one order of magnitude larger than that in 316L stainless steel or tungsten. The removal ratio of hydrogen isotope by helium, neon and argon glow discharge cleaning were 49%, 22% and 6% respectively. These removal ratios were similar to those for the stainless steel, but larger than the tungsten. The removalratio in graphitecan be explainedby both the depth distribution of incident deuterium in the materials and the etching depth.