(FT/P2-21) Definition of Workable Acceptance Criteria for the ITER Divertor Plasma Facing Components through Systematic Experimental Analysis

F. Escourbiac1), M. Richou1), A. Durocher1), S. Constans2), M. Merola3), J. Schlosser1), B. Riccardi4), A. Grosman1)
 
(1) CEA/IRFM, F-13108, Saint-Paul-lez-Durance, France (2) SOM ORTEC, Marseille, France (3) ITER Organization, Cadarache, France (4) Fusion For Energy, Barcelona, Spain

Abstract.  Experience has shown that the most critical part of a high heat flux (HHF) plasma facing component (PFC) is the armour to heat sink joint. An experimental study was launched in order to define acceptance criteria with regards to thermomechanical fatigue of the ITER Divertor PFCs. This study, which includes the manufacturing of samples with calibrated artificial defects relevant with the Divertor design, is reported in this paper. In particular, it was concluded that defects detectable with non-destructive examination (NDE) techniques appeared to be below the threshold of propagation during high heat flux experiments relevant with heat fluxes expected in ITER Divertor. On the basis of these results, a set of acceptance criteria was proposed and applied to the European vertical target medium-size qualification prototypes. It appeared that the ultrasonic and the SATIR NDE techniques allow to be confident in the capability of commissioning respectively W and CFC components reaching the required design values of the ITER Divertor PFCs: 98% of the inspected CFC monoblocks and 100% of W monoblock and flat tiles elements were declared acceptable.

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