%0 Journal Article
%A De Temmerman, G.
%A Morgan, T. W.
%A van Eden, G. G.
%A de Kruif, T.
%A Wirtz, M.
%A Matejicek, J.
%A Chraska, T.
%A Pitts, R. A.
%A Wright, G. M.
%T Effect of High-flux H/He Plasma Exposure on Tungsten Damage Due to Transient Heat Loads
%J Journal of nuclear materials
%V 463
%@ 0022-3115
%C Amsterdam [u.a.]
%I Elsevier Science
%M FZJ-2015-07455
%P 198 - 201
%D 2015
%X The thermal shock behaviour of tungsten exposed to high-flux plasma is studied using a high-power laser. The cases of laser-only, sequential laser and hydrogen (H) plasma and simultaneous laser plus H plasma exposure are studied. H plasma exposure leads to an embrittlement of the material and the appearance of a crack network originating from the centre of the laser spot. Under simultaneous loading, significant surface melting is observed. In general, H plasma exposure lowers the heat flux parameter (FHF) for the onset of surface melting by ∼25%. In the case of He-modified (fuzzy) surfaces, strong surface deformations are observed already after 1000 laser pulses at moderate FHF = 19 MJ m−2 s−1/2, and a dense network of fine cracks is observed. These results indicate that high-fluence ITER-like plasma exposure influences the thermal shock properties of tungsten, lowering the permissible transient energy density beyond which macroscopic surface modifications begin to occur.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000358467200033
%R 10.1016/j.jnucmat.2014.09.075
%U https://juser.fz-juelich.de/record/279571