- freely available
Coatings 2019, 9(9), 575; https://doi.org/10.3390/coatings9090575
2.1. Test Materials and Solutions
2.2. Magnetite-Deposited Corrosion Coupon
2.3. Immersion Corrosion Tests
2.4. Potentiodynamic Polarizaion Tests
3. Results and Discussion
3.1. Electrodeposited Magnetite Layer on SA508 Substrate
3.2. Immersion Corrosion Behavior
3.3. Potentiodynamic Polarization Curves
- Magnetite in contact with SA508 induced the fast corrosion of SA508. This accelerated corrosion of SA508 by magnetite was more severe in a test solution with sulfate ions.
- Regarding the electrochemical behavior, SA508 and magnetite acted as anodic and cathodic members, respectively, in the coupling system.
- In this coupling system, the corrosion current density of SA508 was increased by a galvanic corrosion mechanism with magnetite.
- Based on the experimental results, galvanic corrosion between magnetite and SA508 is proposed as a new acceleration contributor to the denting of SG tubes in the PWR secondary environment.
Conflicts of Interest
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