D retention in C- and O-contaminated tungsten during D + irradiation
D retention in C- and O-contaminated tungsten during D + irradiation
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DOI：
10.1016/j.jnucmat.2012.04.004
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发表时间：
2012-08
影响因子：
3.1
通讯作者：
J. Roszell;A. Labelle;P. Brodersen;J. Davis;A. A. Haasz-A.
中科院分区：
文献类型：
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作者：
J. Roszell;A. Labelle;P. Brodersen;J. Davis;A. A. Haasz-A.
比较了99.96%纯多晶钨（PCW）箔和掺杂碳、氧杂质的PCW箔在300和500 K下10 eV和500 eV/D ~+辐照时的氘保留率。与纯箔样品相比，污染箔在500 K下显示出减少的氘保留，而对于300 K辐照没有差异。X射线光电子能谱（XPS）和二次离子质谱（西姆斯）的未照射的标本显示区域的高度局部化，非均匀的C和O的污染，以及更广泛的区域约1-10%的面积覆盖率的低水平污染。据推测，C/O污染在PCW箔中产生扩散屏障，防止氘从近表面扩散到体中，从而降低在500 K下的总体D保持率。这一发现的氚保留在ITER的影响，如果碳污染，即使在低水平，可以阻止T扩散到散装这将意味着减少T负载在W等离子体面临的组件。
Deuterium retention during 10eV and 500eV/D+irradiations at 300 and 500K was compared for 99.96% pure polycrystalline tungsten (PCW) foils and similar PCW foils contaminated with carbon and oxygen impurities. The contaminated foils showed reduced deuterium retention at 500K compared with pure foil specimens while there was no difference for 300K irradiations. X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy (SIMS) of the unirradiated specimens showed regions of highly localised, non-homogeneous C and O contamination as well as a broader region of low level contamination of about 1–10% areal coverage. It is hypothesised that the C/O contamination creates a diffusion barrier in the PCW foil preventing deuterium from diffusing from the near surface into the bulk, thus reducing overall D retention at 500K. This finding has implications for tritium retention in ITER; if carbon contamination even at low levels can impede T diffusion into the bulk it would mean reduced T loading in W plasma-facing components.