Structure, tritium depth profile and desorption from ‘plasma-facing’ beryllium materials of ITER-Like-Wall at JET

• DOI: 10.1016/j.nme.2017.03.017
• Publication Date: 2017-03-16T18:01:23Z
• Authors: E. Pajuste; G. Kizane; A. Vitins; I. Igaune; L. Avotina; R. Zarins
• Keywords: Fusion power

Tritium depth profile and its temperature programmed desorption rate were determined for selected samples cut out of beryllium tiles removed from the Joint European Torus vacuum vessel during 2012 shut down. A dissolution method under controlled conditions was used to determine tritium in samples, whereas experiments performed assess release pattern. Released measured using a proportional gas flow detector. Prior experiments, plasma-facing surfaces studied by scanning electron microscopy energy dispersive X-ray spectroscopy. Experimental results revealed that > 95% localized top 30 – 45 µm 'plasma-facing' surface, however, possible presence up 100 cannot be excluded. During at 4.8 K/min purge He + 0.1% H2 started below 475 K, most intense occurred 725 915 K degree detritiation 91% can obtained upon reaching 1075 K. The total activity range 2 32 kilo Becquerel per square centimetre surface area.