Corrosion Inhibiting Mechanism of Nitrite Ion on the Passivation of Carbon Steel and Ductile Cast Iron for Nuclear Power Plants

Figure 11

Elemental distribution analyzed by EPMA on the surface of ductile cast iron corroded in simulated cooling water (10,000 ppm NaNO₂) at 25°C for 72 hours; (a) SEM image, (b) Fe, (c) C, (d) O, and (e) N.

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