A study of the effect of nitrogen and molybdenum in the corrosion inhibition of austenitic stainless steel.

摘要

The synergistic effect of N and Mo in remarkably improving the corrosion resistance of austenitic stainless steels in Cl;Since nitrates and nitrites are known to be powerful corrosion inhibitors, the possibility that alloyed nitrogen was capable of oxidizing to either of these species was considered. Nitrate was found to be unstable at all potentials considered provided that the metal was exposed directly to the solution. This resulted in clear evidence that alloyed nitrogen does not oxidize to NO;Enrichment of metallic Ni beneath the passive films of austenitic stainless steels was observed. This enrichment increased with a small addition of Mo with N. Evidence was found of the formation of stable intermetallic phase consisting of a mixed Mo-Ni nitride.;The passive films of Mo bearing austenitic stainless steels polarized in acidic Cl;The nitrogen species observed in the passive films of all austenitic stainless steels studied were a surface nitride and NH