Abstract
The slow strain rate tensile (SSRT) tests were conducted on the cold-rolled Inconel 600 alloy with different amounts of cold work (CW), 10%, 20% and 30% respectively at a nominal strain rate 1×10-6/sec in simulated BWR coolant environment. The dynamic strain aging (DSA) behavior at 200, 250, 275 and 300℃ was studied by two characteristics of serrations, stress increment (△σ) and aging time (△t), except for the observation of mechanical properties. Serrated flow was observed in all stress-strain curves which was one of the DSA manifestations. For the SSRT tests at 200℃, except the curve for the 10% CW Alloy 600 showed a combination of A-, B- and C- type serrations, type A+B serrations were observed for the as-received, 20% CW and 30% CW Alloy 600. Type B serrations were observed for those tested at the temperatures range of 250℃-300℃. At 200℃, the cold-rolled Alloy 600 showed a minimum elongation, but a maximum the reduction of area, and a minimum strain hardening exponent. These results showed the “blue brittleness” feature and could be accounted for by the localized deformation induced by DSA effect. Moreover, the stress increment (△σ) and aging time (△t) significantly increased with increasing strain for the 30% CW Alloy 600 tested at 200℃, it could be concluded that the interactions between solute atoms and dislocations in oxygenated water environment exacerbated the mechanical properties most.