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

Figure 10

XPS depth profile ((a), (b), and (c)) and N1s peaks ((a′), (b′), and (c′)) of the surface film formed in ((a), (a′)) 100k ppm + tap water, ((b), (b′)) 100k ppm TEA + tap water, and ((c), (c′)) 1k ppm + 2.5k ppm TEA + tap water.