TY  - CONF
A1  - Günther, Tobias
T1  - Plasma reheating in LIBS with electric discharge to detect halogens in low concentrations
N2  - The Laser-induced Breakdown Spectroscopy (LIBS) is an useful analytical technique for the chlorine detection in building materials, specifically in the reinforcement concrete. If chlorine exceeds a specific concentration threshold, the result can be pitting corrosion of the reinforcement, which affects the stability and lifetime of building structures like marine constructions, bridges or parking decks. The critical chlorine content based to cement is 0.4 wt.-% based to the cement for reinforced concrete. The ingress of chlorides from sea water or de-icing salt leads to corrosion of the reinforcement.
The chlorine spectral line Cl I at 837.59 nm shows a good performance in helium atmosphere. For measurements without helium we used a electric discharge setup to reheat the Laser-induced plasma with a voltage below 100 V. In this case the reheating shows an increasing chlorine emission in air atmosphere. 
This work shows chlorine calibration curves with LIBS in a helium flow and LIBS with electric discharge reheating in air atmosphere. The determination of the limit of detection (LOD) for both setups and the measurement results of a drill core sample with a quantitative chlorine ingress profile will be presented.
T2  - Xth international conference on Laser-Induced Breakdown Spectroscopy
CY  - Atlanta, GA, USA
DA  - 21.10.2018
KW  - LIBS
KW  - Laser induced plasma
KW  - Plasma reheating
KW  - Electric discharge
PY  - 2018
AN  - OPUS4-46797
LA  - eng
AD  - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER  -