Planning and use of condition-dependent NDT for the interaction between fracture mechanics and quantitative NDT

The proof of safety for reactor components is generally based on non-destructive testing results, which much be evaluated in reference to their safety relevance. The use of fracture mechanics concepts in flaw evaluations requires the quantification of the dependencies between flaw geometry, material characteristics, and load condition. The solution consists of the combination of optimal test preparation using computer-aided design software modules and modeling of the inspection, a quantitative flaw testing using qualified reconstruction methods and qualification procedures of the material parameters like fracture toughness. Besides the discussion of the condition-dependent strategies of lifetime management many results from large-scale round-robin testing concerning crack initiation parameters versus fracture toughness or J-integral or ray tracing in connection with defect sizing in a CAD-environment are shown.