The Use of Charpy/Fracture Toughness Correlations in the FITNET Procedure

In an ideal situation, fracture toughness data to be used in structural integrity assessments are generated through the use of appropriate fracture mechanics-based toughness tests. In reality, such data are often not available or cannot be easily obtained due to lack of material or the impracticability of removing material from the actual structure. In such circumstances, and in the absence of appropriate historical data, the use of correlations between Charpy impact energy and fracture toughness can provide the fracture toughness value to be used in the assessment. The FITNET (Fitness-for-Service) procedure, presently being developed in the frame of a European Thematic Network, includes a section which deals with the use of empirical correlations between Charpy and fracture toughness data. This paper will outline the contents of this chapter, along with some examples of application of selected correlations to actual test data.