Speaker
Alexey Popkov
(Plasma Physics Department)
Description
Lithium is considered as a promising material for plasma-facing components (PFC) in future fusion devices. A number of experiments have already demonstrated positive effects of lithization and using of Li based PFCs on plasma operation. During operation of the machine, lithium is deposited on the surrounding walls and in shadowed areas. One can expect a high concentration of hydrogen isotopes in the resulting films due to good getter properties of lithium. Therefore, co-deposition of hydrogen isotopes and lithium should be investigated.
The Li-D films were co-deposited in magnetron discharge in deuterium. Deuterium accumulation in the films was measured in-situ by means of thermal desorption spectroscopy (TDS). The deuterium concentration in the films was calculated to be 10-20 at. %. The main part of deuterium released in one sharp peak with the maximum at ~710 K.
It was also demonstrated that deuterium can release from lithium films even at room temperature in the case of interaction with water vapour or with air. Interaction with other atmospheric gases (oxygen, nitrogen) is much weaker and did not lead to significant deuterium release at room temperature.
The dynamics of deuterium release during interaction with water vapor was also monitored by quadrupole mass-spectrometer. At the pressure of 1 Pa, significant part of deuterium released already during first several minutes. After 30 minutes of exposure almost no deuterium remained in the film.
Co-authors
Alexander Pisarev
(Plasma Physics Department, National Research Nuclear University MEPhI, Moscow, Kashirskoe highway, 31, Russian Federation)
Alexey Popkov
(Plasma Physics Department, National Research Nuclear University MEPhI, Moscow, Kashirskoe highway, 31, Russian Federation)
Stepan Krat
(Plasma Physics Department, National Research Nuclear University MEPhI, Moscow, Kashirskoe highway, 31, Russian Federation)
Yana Vasina
(Plasma Physics Department, National Research Nuclear University MEPhI, Moscow, Kashirskoe highway, 31, Russian Federation)
Yuri Gasparyan
(Plasma Physics Department, National Research Nuclear University MEPhI, Moscow, Kashirskoe highway, 31, Russian Federation)
