THE STUDY DEVELOPMETN ON CHEMICAL EROSION OF GRAPHITEBOMBARDED BY DEUTERIUM ION BEAM

On the study of the chemical sputtering temperature characteristic of SMF 800 graphite first wall,a further study was carried out with fresh SMF 800 graphite,G3 graphite,SiC and boronized graphite.The SMF 800 graphite boronized with carborane （C ₂B ₁₀ H ₁₂ ）-helium glow discharge in HL 1M TOKAMAK was optimized it possesses the best antichemical-erosion character,the releasing rate of CD₄ was lower one order than that of SMF 800 graphite,and the releasing peak temperature shifted in the vicinity of 650 K.By rotating graphite sample with a small angle,a small angle profile of CD₄ releasing from the graphite radiated with a deuterium beam of 1.3 μA/3 keV was observed.With a 45° incident deuterium ion beam,the released CD₄ peak was positioned at 1° right side of the normal sample with a 5° divergence angle to the normal sample,the releasing rate of CD₄ wad decreased 7% approximatly,being decreasing faster one order than the cosine law.