Studies of tritiated co-deposited layers in TFTR

Abstract

Abstract:Plasma facing components in TFTR contain an important record of plasma wall interactions in reactor grade DT plasmas. Tiles, flakes, wall coupons, a stainless steel shutter and dust samples have been retrieved from the TFTR vessel for analysis. Selected samples have been baked to release tritium and assay the tritium content. The in-vessel tritium inventory is estimated to be 0.56 g and is consistent with the in-vessel tritium inventory derived from the difference between tritium fueling and tritium exhaust. The distribution of tritium on the limiter and vessel wall showed complex patterns of co-deposition. Relatively high concentrations of tritium were found at the top and bottom of the bumper limiter, as predicted by earlier BBQ modeling.

Assessment of the heating technique as a possible ex situ detritiation method for carbon wall materials from fusion machines

“…The four tiles were retrieved from the Bay K of the inner limiter of TFTR after exposure to D-D and D-T plasmas [7]. The 4D CFC tiles are woven with yarns oriented in four directions giving to the microstructure a tetrahedral shape.…”

Hydrogen release from deposition layers formed from 316 stainless steel by hydrogen plasma sputtering

“…Actually, dust consisting Fe, Ni and Cr has been observed in the LHD [1]. Many studies about hydrogen retention in carbon deposition layers have been performed [2][3][4]. However, hydrogen trapping in metallic deposition layers has not been studied sufficiently so far.…”

Neutron elastic recoil detection for hydrogen isotope analysis in fusion materials

“…The study of the behavior is important for the design of the fuel recycling, plasma control, safe management of tritium inventory, etc. If carbon-based materials as PFC, co-deposited layers of carbon compounds are formed with the thickness of several tens of micrometers on PFC surfaces due to plasma-wall interactions [1][2][3][4]. Therefore, it is necessary to measure hydrogen isotope depth profiles in these layers.…”