Abstract
Delayed hydride cracking (DHC) velocity was determined at 203, 227, 250 and 283 °C using 17 mm width curved compact toughness specimens machined from an unirradiated Zr–2.5 wt.% Nb pressure tube spool, gaseously charged with 60 ppm of hydrogen by weight. Single CT specimen was used to determine DHC velocity at a constant temperature for a range of stress intensity factor ( K I) obtained by load drop method. For a given temperature and K I > 15 MPa m 1/2, DHC velocity was found to be practically independent of K I. For 15 > K I > 10 MPa m 1/2, DHC velocity decreased significantly with decrease in stress intensity factor and extrapolation of the data suggested the threshold stress intensity factor to be about 9–11 MPa m 1/2 in the aforementioned temperature range. The activation energy associated with DHC was observed to be 35.1 kJ/mol.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
