The development of structural integrity criteria for austenitic components

The high ductility and resistance to tearing of austenitic stainless steels, allied to the geometry and loading conditions of the European fast reactor (EFR), result in the prediction of large critical through-thickness crack sizes for EFR components. Based on this understanding of large critical crack sizes, simplified methods have been developed for the assessment of the leak-before-break behaviour of these components. The methods described avoid the need for detailed analysis of crack shape development during cyclic loading, and thus greatly reduce the calculational requirements compared with more common methods used for the assessment of known or postulated defects in high energy pressurised components. Simplifications used in the assessment of leak-tightness in EFR components are also identified.