Pitting potentials in sodium chloride solution have been measured potentiodynamically for Ni-Cr-Fe overlay weld alloys with dispersed NbC on a carbon steel formed by plasuma transferred arc method. The presence of NbC in the alloys with Fe content more than 40% caused an electronegative shift in pitting potential, and the morphology of the localized attack was found hemisphere or heneycomb. With Fe content less than 5%, the pits of the alloys containing no NbC had crystallographic attack with

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... -rich phases undissolved. As NbC content was increased, the pitting potential shifted in electropositive direction and the anodic dissolution was uniform with no pitting. The Ni-Cr-Fe overlay weld alloys with dispersed 40% NbC was coverded with a Cr-Nb-Fe-C composition film after anodizing at 1.0V vs. Ag/AgCl and then had higher resistance to pitting corrosion.