Comparison of tungsten nano-tendrils grown in Alcator C-Mod and linear plasma devices
Growth of tungsten nano-tendrils (“fuzz”) has been observed for the first time in the divertor region of a high-power density tokamak experiment. After 14 consecutive helium L-mode discharges in Alcator C-Mod, the tip of a tungsten Langmuir probe at the outer strike point was fully covered with a la...
Main Authors: | , , , , , , , , , , |
---|---|
Other Authors: | |
Format: | Article |
Language: | en_US |
Published: |
Elsevier
2015
|
Online Access: | http://hdl.handle.net/1721.1/99468 https://orcid.org/0000-0002-9001-5606 https://orcid.org/0000-0002-8753-1124 https://orcid.org/0000-0002-7841-9261 https://orcid.org/0000-0002-0450-9731 |
_version_ | 1826188098150596608 |
---|---|
author | Bystrov, K. De Temmerman, G. Wright, Graham Brunner, Daniel Frederic Labombard, Brian Lipschultz, Bruce Woller, Kevin Benjamin Baldwin, M. J. Doerner, R. P. Terry, James L Whyte, Dennis G |
author2 | Massachusetts Institute of Technology. Department of Nuclear Science and Engineering |
author_facet | Massachusetts Institute of Technology. Department of Nuclear Science and Engineering Bystrov, K. De Temmerman, G. Wright, Graham Brunner, Daniel Frederic Labombard, Brian Lipschultz, Bruce Woller, Kevin Benjamin Baldwin, M. J. Doerner, R. P. Terry, James L Whyte, Dennis G |
author_sort | Bystrov, K. |
collection | MIT |
description | Growth of tungsten nano-tendrils (“fuzz”) has been observed for the first time in the divertor region of a high-power density tokamak experiment. After 14 consecutive helium L-mode discharges in Alcator C-Mod, the tip of a tungsten Langmuir probe at the outer strike point was fully covered with a layer of nano-tendrils. The depth of the W fuzz layer (600 ± 150 nm) is consistent with an empirical growth formula from the PISCES experiment. Re-creating the C-Mod exposures as closely as possible in Pilot-PSI experiment can produce nearly-identical nano-tendril morphology and layer thickness at surface temperatures that agree with uncertainties with the C-Mod W probe temperature data. Helium concentrations in W fuzz layers are measured at 1–4 at.%, which is lower than expected for the observed sub-surface voids to be filled with several GPa of helium pressure. This possibly indicates that the void formation is not pressure driven. |
first_indexed | 2024-09-23T07:54:33Z |
format | Article |
id | mit-1721.1/99468 |
institution | Massachusetts Institute of Technology |
language | en_US |
last_indexed | 2024-09-23T07:54:33Z |
publishDate | 2015 |
publisher | Elsevier |
record_format | dspace |
spelling | mit-1721.1/994682023-02-26T02:25:38Z Comparison of tungsten nano-tendrils grown in Alcator C-Mod and linear plasma devices Bystrov, K. De Temmerman, G. Wright, Graham Brunner, Daniel Frederic Labombard, Brian Lipschultz, Bruce Woller, Kevin Benjamin Baldwin, M. J. Doerner, R. P. Terry, James L Whyte, Dennis G Massachusetts Institute of Technology. Department of Nuclear Science and Engineering Massachusetts Institute of Technology. Plasma Science and Fusion Center Wright, Graham Brunner, Daniel Frederic Labombard, Brian Lipschultz, Bruce Terry, James L. Whyte, Dennis G. Woller, Kevin Benjamin Growth of tungsten nano-tendrils (“fuzz”) has been observed for the first time in the divertor region of a high-power density tokamak experiment. After 14 consecutive helium L-mode discharges in Alcator C-Mod, the tip of a tungsten Langmuir probe at the outer strike point was fully covered with a layer of nano-tendrils. The depth of the W fuzz layer (600 ± 150 nm) is consistent with an empirical growth formula from the PISCES experiment. Re-creating the C-Mod exposures as closely as possible in Pilot-PSI experiment can produce nearly-identical nano-tendril morphology and layer thickness at surface temperatures that agree with uncertainties with the C-Mod W probe temperature data. Helium concentrations in W fuzz layers are measured at 1–4 at.%, which is lower than expected for the observed sub-surface voids to be filled with several GPa of helium pressure. This possibly indicates that the void formation is not pressure driven. United States. Dept. of Energy (Award DE-SC00-02060) 2015-10-27T14:22:45Z 2015-10-27T14:22:45Z 2013-01 Article http://purl.org/eprint/type/JournalArticle 00223115 http://hdl.handle.net/1721.1/99468 Wright, G.M., D. Brunner, M.J. Baldwin, K. Bystrov, R.P. Doerner, B. Labombard, B. Lipschultz, et al. “Comparison of Tungsten Nano-Tendrils Grown in Alcator C-Mod and Linear Plasma Devices.” Journal of Nuclear Materials 438 (July 2013): S84–S89. https://orcid.org/0000-0002-9001-5606 https://orcid.org/0000-0002-8753-1124 https://orcid.org/0000-0002-7841-9261 https://orcid.org/0000-0002-0450-9731 en_US http://dx.doi.org/10.1016/j.jnucmat.2013.01.013 Journal of Nuclear Materials Creative Commons Attribution-Noncommercial-NoDerivatives http://creativecommons.org/licenses/by-nc-nd/4.0/ application/pdf Elsevier MIT Web Domain |
spellingShingle | Bystrov, K. De Temmerman, G. Wright, Graham Brunner, Daniel Frederic Labombard, Brian Lipschultz, Bruce Woller, Kevin Benjamin Baldwin, M. J. Doerner, R. P. Terry, James L Whyte, Dennis G Comparison of tungsten nano-tendrils grown in Alcator C-Mod and linear plasma devices |
title | Comparison of tungsten nano-tendrils grown in Alcator C-Mod and linear plasma devices |
title_full | Comparison of tungsten nano-tendrils grown in Alcator C-Mod and linear plasma devices |
title_fullStr | Comparison of tungsten nano-tendrils grown in Alcator C-Mod and linear plasma devices |
title_full_unstemmed | Comparison of tungsten nano-tendrils grown in Alcator C-Mod and linear plasma devices |
title_short | Comparison of tungsten nano-tendrils grown in Alcator C-Mod and linear plasma devices |
title_sort | comparison of tungsten nano tendrils grown in alcator c mod and linear plasma devices |
url | http://hdl.handle.net/1721.1/99468 https://orcid.org/0000-0002-9001-5606 https://orcid.org/0000-0002-8753-1124 https://orcid.org/0000-0002-7841-9261 https://orcid.org/0000-0002-0450-9731 |
work_keys_str_mv | AT bystrovk comparisonoftungstennanotendrilsgrowninalcatorcmodandlinearplasmadevices AT detemmermang comparisonoftungstennanotendrilsgrowninalcatorcmodandlinearplasmadevices AT wrightgraham comparisonoftungstennanotendrilsgrowninalcatorcmodandlinearplasmadevices AT brunnerdanielfrederic comparisonoftungstennanotendrilsgrowninalcatorcmodandlinearplasmadevices AT labombardbrian comparisonoftungstennanotendrilsgrowninalcatorcmodandlinearplasmadevices AT lipschultzbruce comparisonoftungstennanotendrilsgrowninalcatorcmodandlinearplasmadevices AT wollerkevinbenjamin comparisonoftungstennanotendrilsgrowninalcatorcmodandlinearplasmadevices AT baldwinmj comparisonoftungstennanotendrilsgrowninalcatorcmodandlinearplasmadevices AT doernerrp comparisonoftungstennanotendrilsgrowninalcatorcmodandlinearplasmadevices AT terryjamesl comparisonoftungstennanotendrilsgrowninalcatorcmodandlinearplasmadevices AT whytedennisg comparisonoftungstennanotendrilsgrowninalcatorcmodandlinearplasmadevices |