%0 Journal Article
%A Panayotis, S.
%A Hirai, T.
%A Barabash, V.
%A Durocher, A.
%A Escourbiac, F.
%A Linke, J.
%A Loewenhoff, Th.
%A Merola, M.
%A Pintsuk, G.
%A Uytdenhouwen, I.
%A Wirtz, Marius
%T Self-castellation of tungsten monoblock under high heat flux loading and impact of material properties
%J Nuclear materials and energy
%V 12
%@ 2352-1791
%C Amsterdam [u.a.]
%I Elsevier
%M FZJ-2017-06248
%P 200-204
%D 2017
%X In the full-tungsten divertor qualification program at ITER Organization, macro-cracks, so called self-castellation were found in a fraction of tungsten monoblocks during cyclic high heat flux loading at 20MW/m2. The number of monoblocks with macro-cracks varied with the tungsten products used as armour material. In order to understand correlation between the macro-crack appearance and W properties, an activity to characterize W monoblock materials was launched at the IO. The outcome highlighted that the higher the recrystallization resistance, the lower the number of cracks detected during high heat flux tests. Thermo-mechanical finite element modelling demonstrated that the maximum surface temperature ranges from 1800 °C to 2200 °C and in this range recrystallization of tungsten occurred. Furthermore, it indicated that loss of strength due to recrystallization is responsible for the development of macro-cracks in the tungsten monoblock.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000417293300027
%R 10.1016/j.nme.2016.10.025
%U https://juser.fz-juelich.de/record/837279