Use of the failure assessment diagram to deduce ductile fracture toughness of the RAFM steel EUROFER97

In the current work we use the failure assessment diagram (R6) to deduce ductile fracture toughness for the reduced activation ferritic/martensitic steel EUROFER97 by applying Small Specimen Testing Technology. Fracture parameters have been determined in quasi-static three-point-bend experiments. The fracture toughness results obtained with option 1 curve of R6 are sensibly independent of specimen geometry, constraint state and initial crack length and agree well with the results obtained by the analysis of crack resistance curves. Application of option 2 curve of R6 results into less conservative fracture toughness values.