Abstract：Effect of passive film quality on corrosion resistance of 304 austenitic stainless steel after air exposure and chemical passivation was investigated by using electrochemical impedance spectra. A novel inspection of the film quality was proposed based on cathodic reduction and chromaticity inspection. The results show that the compactness of passive film and corrosion resistance for the sample after chemical passivation are superior to that after air exposure. The chromaticity measurement is dependent on the applied potential for the samples after air exposure. The chromaticity measured value increases with decreasing potentials when the applied potential is lower than the reduction potential of outer Fe-rich oxide in passive film. However, the chromaticity for the samples after chemical passivation is close to 0. Based on cyclic voltammetry, it reveals that the chemical passivation improves the corrosion resistance of 304 stainless steel by enhancing the compactness of inner Cr-rich oxide in passive film. Experimental results suggest that the chromaticity inspection could be utilized to numerically characterize the quality of passive film.
程从前, 付琴琴, 曹铁山, 赵杰. 钝化膜质量对奥氏体不锈钢耐蚀性的影响及显色检测[J]. 材料工程, 2013, (8): 65-69.
CHENG Cong-qian, FU Qin-qin, CAO Tie-shan, ZHAO Jie. Effect of Passive Film Quality on Corrosion Resistance of Austenitic Stainless Steel and Chromaticity Inspection. Journal of Materials Engineering, 2013, (8): 65-69.
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