Behavior of impurities in the scrape-off layer under long duration discharges in TRIAM-1M

N. Yoshida, Kazutoshi Tokunaga, T. Fujiwara, K. Tawara, T. Muroga, S. Itoh

Research output: Contribution to journalArticle

16 Citations (Scopus)

Abstract

In order to understand the behavior of impurities under long pulse operation in the TRIAM-1M and to extract issues for the plasma facing materials for steady state tokamaks, deposition of impurities on a collector probe set in the SOL and the damage of the limiters were examined. Mo limiters were the major sources of metallic impurities. Due to interaction with the edge plasma during a long pulse discharge, the surfaces of the limiters were slightly melted and evaporated Mo intruded continuously into the main plasma. In the SOL there was Fe, Cr and Ni sputtered from the wall, that could hardly penetrate into the main plasma due to the trapping effect of the poloidal limiters. Large cavities and cracks were formed at the interface between the unmelted matrix and the melted layer of the limiters. Such defects parallel to the surface reduce the effective thermal conductivity and thus enhance the damage and evaporation of impurities.

Original languageEnglish
Pages (from-to)415-420
Number of pages6
JournalJournal of Nuclear Materials
Volume196-198
Issue numberC
DOIs
Publication statusPublished - Dec 1 1992

Fingerprint

Limiters
Impurities
impurities
Plasmas
damage
pulses
accumulators
Beam plasma interactions
thermal conductivity
cracks
trapping
evaporation
Thermal conductivity
Evaporation
cavities
probes
defects
Cracks
matrices
Defects

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics
  • Nuclear Energy and Engineering
  • Materials Science(all)

Cite this

Behavior of impurities in the scrape-off layer under long duration discharges in TRIAM-1M. / Yoshida, N.; Tokunaga, Kazutoshi; Fujiwara, T.; Tawara, K.; Muroga, T.; Itoh, S.

In: Journal of Nuclear Materials, Vol. 196-198, No. C, 01.12.1992, p. 415-420.

Research output: Contribution to journalArticle

Yoshida, N. ; Tokunaga, Kazutoshi ; Fujiwara, T. ; Tawara, K. ; Muroga, T. ; Itoh, S. / Behavior of impurities in the scrape-off layer under long duration discharges in TRIAM-1M. In: Journal of Nuclear Materials. 1992 ; Vol. 196-198, No. C. pp. 415-420.
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