A better nanochannel tungsten film in releasing helium atoms
G Wei and JW Li and YG Li and HQ Deng and CZ Jiang and F Ren, JOURNAL OF NUCLEAR MATERIALS, 532, 152044 (2020).
DOI: 10.1016/j.jnucmat.2020.152044
Discovering highly radiation resistant plasma facing materials (PFM) is an urgent target for nuclear fusion reactor. In our previous work, a new PFM (nanochannel tungsten film) that consists of many tungsten crystal columns was found having excellent radiation tolerant properties. In the present work, three tungsten columns whose top surfaces are 100, 110 and 111-oriented were studied by molecular dynamics simulations and density functional theory calculations. We find that the tungsten columns whose top surfaces are 100-oriented retain fewer helium atoms than the tungsten columns whose top surfaces are 110 or 111-oriented. Moreover, the microstructural changes of tungsten columns whose top surfaces are 100-oriented are smaller than others after high helium fluence exposure, which indicates that the nanochannel tungsten film maybe more suitable than bulk tungsten for plasma facing material in releasing helium atoms and delaying the formation of "fuzz" structure. The results reported here can help us to design a better radiation resistant plasma facing material in the future. (C) 2020 Elsevier B.V. All rights reserved.
Return to Publications page