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用动电位极化、恒电位极化及交流阻抗技术研究了309不锈钢及其溅射纳米涂层在0.25 mol/L Na2SO4 + 0.05 mol/L H2SO4 和0.5 mol/L NaCl + 0.05 mol/L H2SO4溶液中的电化学腐蚀行为。结果表明，在0.25 mol/L Na2SO4 + 0.05 mol/L H2SO4溶液中，纳米涂层和不锈钢形成的钝化膜的抗腐蚀能力差别较小；而在0.5 mol/L NaCl + 0.05 mol/L H2SO4溶液中，纳米涂层的耐点蚀性能有了很大提高，这是由于纳米化使涂层表面形成的钝化膜更加致密、更加稳定；同时，通过容抗测量研究了纳米涂层和不锈钢钝化膜的电子结构，并提出了相应的腐蚀机制。

Nanocrystallized 309 stainless steel coating has been fabricated on glass substrate by DC magnetron sputtering. The coating, with an average grain size less than 50 nm, had ferritic （bcc） structure rather than the austenitic （fcc） structure of the bulk steel. The electrochemical corrosion behavior of the nano-crystalline （NC) coating and the bulk steel in solutions of 0.25 mol/L Na2SO4 + 0.05 mol/L H2SO4 and 0.5 mol/L NaCl + 0.05 mol/L H2SO4 was investigated by using potentiodynamic polarization,potentiostatic polarization and capacitance mea?鄄surement. The results showed that the corrosion behavior of the NC 309SS coating and 309SS bulk steel depend?鄄ed on the composition of the solutions. In the Na2SO4 solution there was only a little difference between the corro?鄄sion resistance of the passive films on the NC coating and the bulk steel. However, in the solution with chloride ions, the localized corrosion resistance of 309SS was greatly enhanced by nanocrystallization due to the formation of a compact and stable passive film on the NC coating. The electronic structure of the passive film formed on the NC coating and on the bulk steel was analyzed by means of capacitance measurements, and a corrosion mecha?鄄nism is proposed.