Atomistic simulations of tungsten surface evolution under low-energy neon implantation

Journal Article · Wed Mar 02 04:00:00 EST 2016 · Nuclear Fusion

DOI:https://doi.org/10.1088/0029-5515/56/4/046008· OSTI ID:1348299

Backman, Marie ^[1]; Hammond, Karl D. ^[1]; Sefta, Faiza ^[2]; Wirth, Brian D. ^[3]

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1. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Nuclear Engineering
2. Univ. of California, Berkeley, CA (United States). Dept. of Nuclear Engineering
3. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Nuclear Engineering; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Tungsten is a candidate material for the divertor of fusion reactors, where it will be subject to a high flux of particles coming from the fusion plasma as well as a significant heat load. Under helium plasma exposure in fusion-reactor-like conditions, a nanostructured morphology is known to form on the tungsten surface in certain temperature and incident energy ranges, although the formation mechanism is not fully established. A recent experimental study (Yajima et al 2013 Plasma Sci. Technol. 15 282-6) using neon or argon exposure did not produce similar nanostructure. Here, this article presents molecular dynamics simulations of neon implantation in tungsten aimed at investigating the surface evolution and elucidating the role of noble gas mass in fuzz formation. Finally, in contrast to helium, neon impacts can sputter both tungsten and previously implanted neon atoms. The shorter range of neon ions, along with sputtering, limit the formation of large bubbles and likely prevents nanostructure formation.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)
• DOE Contract Number: AC05-00OR22725; SC0002060; SC0006661
• OSTI ID: 1348299
• Journal Information: Nuclear Fusion, Journal Name: Nuclear Fusion Journal Issue: 4 Vol. 56; ISSN 0029-5515
• Publisher: IOP Science
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
Plasmas
Transition-Metals
molecular dynamics simulations
plasma surface interaction
surface structure and morphology
tungsten