Non-destructive testing of divertor components

This task within the EU R&D for ITER had two main objectives: (1) qualification of inspection procedures for plasma facing components (PFC), (2) assessment of the behaviour of calibrated defects under high heat flux (HHF) cyclic loading. The ultimate goal of this work was to demonstrate that the reliable identification of fatal defects by the chosen non-destructive testing (NDT) methods can be achieved. This R&D was carried out according to the following steps: (1) manufacture of a divertor vertical target (VT) prototype with artificial calibrated defects; (2) blind non-destructive round robin test of the prototype; (3) HHF test in FE200 electron beam (EB) facility; (4) post-fatigue blind non-destructive round robin test; (5) destructive examination. The general final conclusion was that the NDT techniques can reliably detect and locate defects having dimensions well below those, which could impair the thermal fatigue lifetime.