Fracture toughness of Zr-2.5wt%N6 pressure tubes

not registered

Measurements of fracture toughness of HT Zr-2.5wt% Nb pressure tubes have been made by study ing internally pressurizing(burst) test specimens and small bending test specimens. These tests were conducted from a viewpoint of the effects of hydrogencontent, hydrideorientation, temperature and crack configuration on the fracture toughness Kc. Results of the experiments showed that Kc decreased with increasing hydrogen content, but it wouid be little affected by hydrogen content at reactor operating temperature. The value of Kc could be quantitatively evaluated by RHC defined by radial hydride content (RHC) perpendicular to the tensile stress, and it decreased with increasing RHC.