Abstract
Pitting corrosions of 3.5NiCrMoV steel and 13Cr steel, the materials used respectively for rotors and blades of low-pressure steam turbines in power plants, are evaluated by anodic polarization tests in the simulated AVT (All Volatile Treatment) water, and also in the waters added with chloride ions (Cl−) and sulfate ions (SO4 2−), at 308 K. It is clarified that the pitting corrosions of 3.5NiCrMoV steel, in addition to the uniform corrosions, are promoted by adding Cl− and SO4 2− ions into the test waters. As for 13Cr steel, the high pitting corrosion resistance is shown in the test water with only SO4 2− ions due to the stable passive film formed on the specimen while the pitting corrosion is remarkably promoted by adding Cl− ions into the water. It is clear that the coexistence of SO4 2− ions with Cl− ions in the test water exhibits an inhibiting effect on the initiation of corrosion pits but also an accelerating effect on the pit growth, for the high-alloyed 13Cr steel.
Published Version (
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