New Mechanism on Synergistic Effect of Nitrite and Triethanolamine Addition on the Corrosion of Ductile Cast Iron

Figure 8

Elemental distribution analyzed by EPMA on the surface of DCI, which was passivated for 72 hours in tap water with 1k ppm + 2.5k ppm TEA at 25°C. (a) SEM image, (b) Fe, (c) C, (d) O, and (e) N.

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