Abstract: IN this paper by means of potentialstatic method secondary passivity of the stainless steel 316 in NaCl solution,which occured while measuring anodic polarization curves is discussed.
The range of Prazak's mechanism on secondary passivity is extended rom transpassive dissolution to pitting corrosion on the base of these experiments. this mechanism is then used in the discussion of secondary passivity in NaCl solution, The conclusion is that secondary passivity can only occu on certain conditions, i.e.on certain material, media and environment.
The both mechanisms of the secondary passivity are like, though the process occurring in H₂SO₄ solution is the transpassive dissolution of the passive layer of stainless steel while the pitting corrosion of the same steel is taken place in NaCl solution.