Clarifying the role of Ce in the corrosion behavior of Fe–36Ni Invar alloy

The effect of Ce on the corrosion behavior of Fe–36Ni Invar alloy was investigated in a 3.5 wt% NaCl solution. The proper addition of Ce enhanced the corrosion resistance. The second-phase particles were gradually transformed in type, size, and number following the addition of Ce, which alleviated the localized corrosion behavior. The appropriate Ce content increased the fraction of low coincident site lattice boundaries. Furthermore, the enhancement of protectiveness and compactness of the passive film was achieved. However, overadded Ce led to the degradation of corrosion resistance. 0.0170 wt% Ce was advised for the sake of the enhancement of corrosion resistance.