U.S. Department of EnergyOffice of Scientific and Technical Information
Elemental and topographical imaging of microscopic variations in deposition on NSTX-U and DIII-D samples2
Abstract
Abstract: Tokamak plasma facing components have surface roughness that can cause microscopic spatial variations in erosion and deposition and hence influence material migration, erosion lifetime, dust and tritium accumulation, and plasma contamination. However high spatial resolution measurements of deposition on the scale of the surface roughness have been lacking to date. We will present elemental images of graphite samples from NSTX-U and DIII-D DiMES experiments performed with a Scanning Auger Microprobe at sub-micron resolution that show strong microscopic variations in deposition and correlate this with 3D topographical maps of surface irregularities. The NSTX-U samples were boronized and exposed to deuterium plasmas and the DiMES samples had localized Al and W films and were exposed to dedicated helium plasmas. Topographical maps of the samples were performed with a 3D confocal optical microscope and compared to the elemental deposition pattern. The results revealed localized deposition concentrated in areas shadowed from the ion flux, incident in a direction calculated (for the DiMES case) by taking account of the magnetic pre-sheath.
- Authors:
- Publication Date:
- Research Org.:
- Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
- Sponsoring Org.:
- U. S. Department of Energy
- Keywords:
- Erosion, Deposition, NSTX-U, DIMES, Plasma-Materials Interaction, Surface Analysis
- OSTI Identifier:
- 1562053
- DOI:
- https://doi.org/10.11578/1562053
Citation Formats
Skinner, C. K., Chrobak, C. P., Kaita, R., and Koel, B. E. Elemental and topographical imaging of microscopic variations in deposition on NSTX-U and DIII-D samples2. United States: N. p., 2019.
Web. doi:10.11578/1562053.
Skinner, C. K., Chrobak, C. P., Kaita, R., & Koel, B. E. Elemental and topographical imaging of microscopic variations in deposition on NSTX-U and DIII-D samples2. United States. doi:https://doi.org/10.11578/1562053
Skinner, C. K., Chrobak, C. P., Kaita, R., and Koel, B. E. 2019.
"Elemental and topographical imaging of microscopic variations in deposition on NSTX-U and DIII-D samples2". United States. doi:https://doi.org/10.11578/1562053. https://www.osti.gov/servlets/purl/1562053. Pub date:Mon Apr 01 00:00:00 EDT 2019
@article{osti_1562053,
title = {Elemental and topographical imaging of microscopic variations in deposition on NSTX-U and DIII-D samples2},
author = {Skinner, C. K. and Chrobak, C. P. and Kaita, R. and Koel, B. E.},
abstractNote = {Abstract: Tokamak plasma facing components have surface roughness that can cause microscopic spatial variations in erosion and deposition and hence influence material migration, erosion lifetime, dust and tritium accumulation, and plasma contamination. However high spatial resolution measurements of deposition on the scale of the surface roughness have been lacking to date. We will present elemental images of graphite samples from NSTX-U and DIII-D DiMES experiments performed with a Scanning Auger Microprobe at sub-micron resolution that show strong microscopic variations in deposition and correlate this with 3D topographical maps of surface irregularities. The NSTX-U samples were boronized and exposed to deuterium plasmas and the DiMES samples had localized Al and W films and were exposed to dedicated helium plasmas. Topographical maps of the samples were performed with a 3D confocal optical microscope and compared to the elemental deposition pattern. The results revealed localized deposition concentrated in areas shadowed from the ion flux, incident in a direction calculated (for the DiMES case) by taking account of the magnetic pre-sheath.},
doi = {10.11578/1562053},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Apr 01 00:00:00 EDT 2019},
month = {Mon Apr 01 00:00:00 EDT 2019}
}