Consequences of PWR primary water oxidation on structural alloys

'Full text:' In the present study, two Ni-Fe-Cr ternary alloys were tested in simulated pressurized water reactor (PWR) primary water at 360oC for 1000 h. The chemical composition of these alloys was chosen to be representative of chromium depleted areas under the oxide scale of industrial alloys such as alloy 600 exposed to the same conditions. The resulting oxidized structures (corrosion scale and underlying metal) were characterized using complementary analytical methods (FEG-SEM, TEM, SIMS, optical microscopy). Analysis of the chemical composition of the metal close to the oxide scale enabled internal oxides as well as oxygen under the oxide layer to be detected. The implications of these results for the intergranular stress corrosion cracking resistance of nickel-base alloys are discussed. (author)