Abstract
The aim of the present study was to develop in situ control methods for
erosion of layers and deposition on the main wall of a fusion reactor.
For this purposes laser induced breakdown spectroscopy (LIBS) was
applied to specially manufactured samples with coatings of known
thickness and composition in vacuum. The whole laser induced spectrum in
range 200–850 nm was recorded for every laser shot. Our results
demonstrated that the equipment used has sufficient sensitivity for
recording of the spectrum during a single laser shot. The diagnostic
lines most suitable for characterization of layers were determined.
Tungsten layer on carbon substrate is detectable and its ablation rate
is 0.5–1 μm per laser pulse. From the recorded spectra it is possible to
estimate tungsten coating thickness, but for a complex coating where
tungsten layer was covered with diamond-like carbon (DLC), tungsten was
spectroscopically not detectable. Additional information about charge
concentration and movement is possible to obtain by measuring the
current pulses in the sample circuit.
Original language | English |
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Pages (from-to) | 1465-1467 |
Number of pages | 3 |
Journal | Fusion Engineering and Design |
Volume | 84 |
Issue number | 7-11 |
DOIs | |
Publication status | Published - 2009 |
MoE publication type | A1 Journal article-refereed |
Event | 25th Symposium on Fusion Technology, SOFT-25 - Rostock, Germany Duration: 15 Sept 2008 → 19 Sept 2008 |
Keywords
- LIBS
- Laser ablation
- Plasma facing materials
- Diagnostics
- Tungsten coating
- Erosion and deposition