Abstract
The ablation and fuel-retention characteristics of
aluminum-tungsten (AlW) and beryllium-tungsten (BeW)
samples have been determined using Laser Induced
Breakdown Spectroscopy (LIBS) and compared to results
obtained using Secondary Ion Mass Spectrometry (SIMS).
The measurements have been made both at vacuum (of the
order of 10-4 Pa) and at 50Pa of argon to especially
enhance the intensities of the spectral lines of H and D.
For reliable evaluation of the ablation rate of the
samples the electron density ne and temperature Te of the
LIBS plasma have been determined with the help of
selected of spectral lines of Be, Al, and W. The electron
density ne has been obtained from Stark broadening lines
of Al I (308.7nm and 394.4nm) and Be II (457.3nm) and Te
from the Saha-Boltzmann plot using W I and W II spectral
lines having a higher value of the energy of upper states
in order to prevent the influence of self-absorption on
the results. The results indicate similar ablation
characteristics between AlW (AlWD) and BeW (BeWD) samples
but the inclusion of deuterium in the coating increases
the ablation rate by a factor of 10 for both sample
types. Concerning fuel retention more than one order of
magnitude less D is retained in the AlWD sample than in
BeWD. In the presence of background argon, the H and D
lines were stronger and more easily distinguishable. This
is a positive sign considering the real application in
ITER where LIBS measurements are foreseen to be done
during maintenance breaks. However the higher pressure
gave a better signal, it is still far from the
measurement conditions planned for ITER which need to be
tested separately.
Original language | English |
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Pages (from-to) | 611-616 |
Number of pages | 6 |
Journal | Nuclear Materials and Energy |
Volume | 12 |
Issue number | June |
Early online date | 2017 |
DOIs | |
Publication status | Published - 2017 |
MoE publication type | A1 Journal article-refereed |
Keywords
- aluminum
- beryllium
- LIBS