Abstract
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. 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. 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.
Original language | English |
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Article number | 046008 |
Journal | Nuclear Fusion |
Volume | 56 |
Issue number | 4 |
DOIs | |
State | Published - Mar 2 2016 |
Externally published | Yes |
Funding
Partial financial support for this work was provided through the Scientific Discovery through Advanced Computing (SciDAC) project on Plasma-Surface Interactions, funded by the U.S. Department of Energy, Offices of Science, Advanced Scientific Computing Research, and Fusion Energy Sciences. Additional funding was provided through the Plasma-Surface Interactions Science Center, funded by the U.S. Department of Energy, Office of Fusion Energy Sciences under award DE-SC0002060 and by the U.S. Department of Energy, Office of Fusion Energy Sciences under award DE-SC0006661
Keywords
- molecular dynamics simulations
- plasma surface interaction
- surface structure and morphology
- tungsten