Effect of crack length-to-width ratio on crack resistance of high Cr-ODS steels at high temperature for fuel cladding application

The aim of the present paper is to provide some insight on their fracture behavior at high temperature and different crack configurations, in particular shallow crack. Crack resistance measurements were performed on a 12%Cr-ODS steel using compact tension specimens at 650 °C considering both shallow and deep crack configurations. Finite element calculations were performed on a typical fuel cladding tube geometry to assess the performances in terms of crack resistance. It is found that the temperature gradient across the wall should be maintained low enough to avoid cracking. After irradiation in corrosive environment, the boundary conditions might be further affected limiting therefore the lifetime of ODS cladding.