A molecular dynamics study of diamond exposed to tritium bombardment for fusion applications

作者：Dunn A R^*; Duffy D M; Stoneham A M

来源：Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms , 2011, 269(14): 1724-1726.

DOI：10.1016/j.nimb.2010.12.009

• Diamond
• Tritium
• Fusion
• Divertor
• Plasma facing material
• High flux

Diamond, with its low atomic number and high thermal conductivity, is being assessed as a possible plasma facing material within a fusion reactor. Molecular dynamics simulations using the AIREBO potential were performed simulating the exposure of diamond to a plasma in conditions similar to those of the divertor region of a tokamak. Diamond surfaces at temperatures of 300 and 600 K were bombarded with 15 eV tritium at a high flux (10(29) ions m(-2) s(-1)). A layer-by-layer etching process was observed which, with the lack of any tritium diffusion though the remaining diamond structure, was responsible for limiting damage, and thus tritium retention, to the top 4-5 diamond layers. Analysis of this damaged region also showed a large amount of residual structure suggesting that bombardment below the physical sputtering threshold (similar to 30 eV) may not lead to amorphisation of the surface.

• 出版日期2011-7-15