skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Nucleation and growth of tungsten nanotendrils grown under divertor-like conditions

Abstract

Tungsten is the primary candidate for plasma-facing materials in the critical regions of a magnetic fusion energy (MFE) device, such as a tokamak. However, tungsten (and many other metals) grow copious nanotendril "fuzz" when exposed to fusion-relevant He-bearing plasmas, and the impact of this fuzz on reactor operation is still unknown. Further, the mechanism of fuzz growth is also poorly understood at present. In order to experimentally probe the growth mechanisms, we developed a new sample preparation technique to examine the interface of individual nanotendril roots with the substrate (substrate/tendril interface) using electron microscopy and measured the grain boundary character distributions (GBCDs) of substrate/tendril interfaces, the GBs within individual tendrils (tendril/tendril interfaces), and GBs within the substrate (substrate/substrate interfaces). We find the substrate/tendril and tendril/tendril GBCDs are essentially indistinguishable, but very different from the substrate/substrate GBCDs, which implies that tendril growth periodically forms new GBs at the substrate/tendril interface, and these GBs are pushed upward to become tendril/tendril interfaces within the fuzz mat. These results will help guide future computational modelling studies to elucidate the details of the growth mechanisms.

Authors:
ORCiD logo [1];  [2];  [2]; ORCiD logo [1]
  1. ORNL
  2. University of California, San Diego
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Fusion Energy Sciences (FES)
OSTI Identifier:
1777822
Alternate Identifier(s):
OSTI ID: 1548076
Grant/Contract Number:  
AC05-00OR22725; FG02-07ER54912
Resource Type:
Accepted Manuscript
Journal Name:
Journal of Nuclear Materials
Additional Journal Information:
Journal Volume: 509; Journal Issue: 0
Country of Publication:
United States
Language:
English

Citation Formats

Wang, Kun, Doerner, R. P., Baldwin, Matthew J., and Parish, Chad. Nucleation and growth of tungsten nanotendrils grown under divertor-like conditions. United States: N. p., 2018. Web. doi:10.1016/j.jnucmat.2018.07.043.
Wang, Kun, Doerner, R. P., Baldwin, Matthew J., & Parish, Chad. Nucleation and growth of tungsten nanotendrils grown under divertor-like conditions. United States. doi:https://doi.org/10.1016/j.jnucmat.2018.07.043
Wang, Kun, Doerner, R. P., Baldwin, Matthew J., and Parish, Chad. Mon . "Nucleation and growth of tungsten nanotendrils grown under divertor-like conditions". United States. doi:https://doi.org/10.1016/j.jnucmat.2018.07.043. https://www.osti.gov/servlets/purl/1777822.
@article{osti_1777822,
title = {Nucleation and growth of tungsten nanotendrils grown under divertor-like conditions},
author = {Wang, Kun and Doerner, R. P. and Baldwin, Matthew J. and Parish, Chad},
abstractNote = {Tungsten is the primary candidate for plasma-facing materials in the critical regions of a magnetic fusion energy (MFE) device, such as a tokamak. However, tungsten (and many other metals) grow copious nanotendril "fuzz" when exposed to fusion-relevant He-bearing plasmas, and the impact of this fuzz on reactor operation is still unknown. Further, the mechanism of fuzz growth is also poorly understood at present. In order to experimentally probe the growth mechanisms, we developed a new sample preparation technique to examine the interface of individual nanotendril roots with the substrate (substrate/tendril interface) using electron microscopy and measured the grain boundary character distributions (GBCDs) of substrate/tendril interfaces, the GBs within individual tendrils (tendril/tendril interfaces), and GBs within the substrate (substrate/substrate interfaces). We find the substrate/tendril and tendril/tendril GBCDs are essentially indistinguishable, but very different from the substrate/substrate GBCDs, which implies that tendril growth periodically forms new GBs at the substrate/tendril interface, and these GBs are pushed upward to become tendril/tendril interfaces within the fuzz mat. These results will help guide future computational modelling studies to elucidate the details of the growth mechanisms.},
doi = {10.1016/j.jnucmat.2018.07.043},
journal = {Journal of Nuclear Materials},
number = 0,
volume = 509,
place = {United States},
year = {2018},
month = {10}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 4 works
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

Formation of helium induced nanostructure ‘fuzz’ on various tungsten grades
journal, September 2010


Formation process of tungsten nanostructure by the exposure to helium plasma under fusion relevant plasma conditions
journal, August 2009


Helium, hydrogen, and fuzz in plasma-facing materials
journal, October 2017


Deuterium retention in tungsten after heavy ion damage and hydrogen isotope exchange in PISCES
journal, August 2014

  • Barton, J. L.; Wang, Y. Q.; Dittmar, T.
  • Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, Vol. 332
  • DOI: 10.1016/j.nimb.2014.02.077

Effect of He on D retention in W exposed to low-energy, high-fluence (D, He, Ar) mixture plasmas
journal, November 2011


Tungsten as material for plasma-facing components in fusion devices
journal, August 2011


Molecular-dynamics analysis of mobile helium cluster reactions near surfaces of plasma-exposed tungsten
journal, October 2015

  • Hu, Lin; Hammond, Karl D.; Wirth, Brian D.
  • Journal of Applied Physics, Vol. 118, Issue 16
  • DOI: 10.1063/1.4933393

Low energy and low fluence helium implantations in tungsten: Molecular dynamics simulations and experiments
journal, March 2016


Spatially dependent cluster dynamics modeling of microstructure evolution in low energy helium irradiated tungsten
journal, August 2014


Loop punching and bubble rupture causing surface roughening —A model for W fuzz growth
journal, January 2014


Atomistic modeling of growth and coalescence of helium nano-bubbles in tungsten
journal, August 2015


Stick–slip behavior identified in helium cluster growth in the subsurface of tungsten: effects of cluster depth
journal, September 2015


Comparison of tungsten nano-tendrils grown in Alcator C-Mod and linear plasma devices
journal, July 2013


Tungsten nano-tendril growth in the Alcator C-Mod divertor
journal, March 2012


Microstructure refinement of tungsten by surface deformation for irradiation damage resistance
journal, January 2014


TEM observation of the growth process of helium nanobubbles on tungsten: Nanostructure formation mechanism
journal, November 2011


Morphologies of tungsten nanotendrils grown under helium exposure
journal, February 2017

  • Wang, Kun; Doerner, R. P.; Baldwin, M. J.
  • Scientific Reports, Vol. 7, Issue 1
  • DOI: 10.1038/srep42315

Grain orientations and grain boundaries in tungsten nonotendril fuzz grown under divertor-like conditions
journal, January 2017


Deuterium retention in tungsten in dependence of the surface conditions
journal, March 2003


LAMDA: Irradiated-Materials Microscopy at Oak Ridge National Laboratory
journal, August 2015

  • Parish, Chad M.; Kiran Kumar, N. A. P.; Snead, Lance L.
  • Microscopy and Microanalysis, Vol. 21, Issue S3
  • DOI: 10.1017/S1431927615005814

Transmission EBSD from 10 nm domains in a scanning electron microscope: TRANSMISSION EBSD IN THE SEM
journal, November 2011


Transmission Kikuchi diffraction in a scanning electron microscope: A review
journal, December 2016

  • Sneddon, Glenn C.; Trimby, Patrick W.; Cairney, Julie M.
  • Materials Science and Engineering: R: Reports, Vol. 110
  • DOI: 10.1016/j.mser.2016.10.001

On the optimum resolution of transmission-electron backscattered diffraction (t-EBSD)
journal, January 2016


Risks of “Cleaning” Electron Backscatter Diffraction Data
journal, March 2010


Sputtering properties of tungsten ‘fuzzy’ surfaces
journal, August 2011


Helium effects on tungsten under fusion-relevant plasma loading conditions
journal, July 2013


A classification of symmetrical grain boundaries
journal, August 1987


Helium bubble bursting in tungsten
journal, December 2013

  • Sefta, Faiza; Juslin, Niklas; Wirth, Brian D.
  • Journal of Applied Physics, Vol. 114, Issue 24
  • DOI: 10.1063/1.4860315

Mechanical properties of micro-sized copper bending beams machined by the focused ion beam technique
journal, September 2005