2015 Volume 56 Issue 12 Pages 1992-1999
The slow strain rate tests were conducted on cold-worked Alloy 600 at a nominal strain rate 1 × 10−6 s−1 in air and in a simulated BWR coolant environment. The dynamic strain aging phenomenon at 200°C, 250°C, 275°C and 300°C was studied. The jerky flows of small and large serration amplitude observed on the stress-strain curves were respectively categorized as type B and D serrations. The serrated flow is more significant for those specimens with lower cold work levels tested at higher temperatures than those with higher cold work levels tested at lower temperatures. For the cold-rolled SSRT specimens tested in the 200°C water environment, the largest reduction of area along with the smallest elongation was observed. It could be accounted for by the localized deformation induced by dynamic strain aging. The strain hardening exponent generally increases with increasing the test temperature and decreases with an increase of the cold work level.