Nanochannel structures in W enhance radiation tolerance
- Wuhan Univ. (China). School of Physics and Technology. Center for Ion Beam Application. Center for Electron Microscopy
- Univ. of California, San Diego, CA (United States). Center for Energy Research
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- Hunan Univ., Changsha (China). Dept. of Applied Physics. School of Physics and Electronics
Developing high performance plasma facing materials (PFMs) is one of the greatest challenges for fusion reactors, because PFMs face unprecedented harsh environments including high flux plasma exposure, fast neutron irradiation and large transmutation gas. Tungsten (W) is considered as one of the most promising PFMs. Rapid accumulation of helium (He) atoms in such environments can lead to the He bubbles nucleation and even the formation of nano- to micro-scale “fuzz” on W surface, which greatly degrade the properties of W itself. The possible ejection of large W particulates into the core plasma can cause plasma instabilities. In this paper, we present a new strategy to address the root causes of bubble nucleation and “fuzz” formation by concurrently releasing He outside of W matrix through the nano-engineered channel structure (nanochannels). Comparing to ordinary bulk W, nanochannel W films with high surface-to-volume ratios are found to not only delay the growth of He bubbles, but also suppress the formation of “fuzz” (less than a half of the “fuzz” thickness formation in bulk W). Finally, molecular dynamic (MD) simulation results elucidate that low vacancy formation energy and high He binding energy in the nanochannel surface effectively help He release and affect He clusters distribution in W during He ion irradiation.
- Research Organization:
- Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
- Sponsoring Organization:
- USDOE; LANL Laboratory Directed Research and Development (LDRD) Program; National Natural Science Foundation of China (NSFC); Fundamental Research Funds for the Central Universities (China); Natural Science Foundation of Hubei Province (China); Univ. of California (United States)
- Grant/Contract Number:
- AC52-06NA25396; 11522543; 11475129; 51771073; 51571153; 2042017kf0194; 2016CFA080; 12-LR-237801; LDRD-20160567ER
- OSTI ID:
- 1440458
- Alternate ID(s):
- OSTI ID: 1548427
- Report Number(s):
- LA-UR-18-24035
- Journal Information:
- Acta Materialia, Vol. 153; ISSN 1359-6454
- Publisher:
- ElsevierCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
Helium flux effects on bubble growth and surface morphology in plasma-facing tungsten from large-scale molecular dynamics simulations
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journal | May 2019 |
Understanding the release of helium atoms from nanochannel tungsten: a molecular dynamics simulation
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journal | June 2019 |
Ion beam analysis of fusion plasma-facing materials and components: facilities and research challenges
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journal | December 2019 |
Irradiation-Dependent Helium Gas Bubble Superlattice in Tungsten
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journal | February 2019 |
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