The corrosion behaviors of copper and copper/titanium galvanic couple （GC） in seawater were studied by electrochemical impedance spectroscopy （EIS） and electrochemical noise （EN） techniques in conjunction with s...The corrosion behaviors of copper and copper/titanium galvanic couple （GC） in seawater were studied by electrochemical impedance spectroscopy （EIS） and electrochemical noise （EN） techniques in conjunction with scanning electron microscopy （SEM） method. The results show that the corrosion process of copper in seawater can be divided into two stages, in which corrosion resistance and SE show the same evolution trend of initial increase and subsequent decrease, while SG changes oppositely. However, the ensemble corrosion process of copper/titanium GC in seawater includes three stages, in which corrosion resistance and SE show the evolution features of initial decrease with a subsequently increase, and the final decrease again;while SG changes oppositely. The potential difference between copper and titanium in their galvanic couple can accelerate the initiation of pitting corrosion of copper, and both the minimum and maximum corrosion potentials of copper/titanium GC are much more positive than those of pure copper.展开更多
Spontaneous electrochemical noise (EN) can be a rich source of information concerning the processes simultaneously occurring on a corroding interface. But the noise signal is often difficult to be analyzed due to the ...Spontaneous electrochemical noise (EN) can be a rich source of information concerning the processes simultaneously occurring on a corroding interface. But the noise signal is often difficult to be analyzed due to the complicated nature of the specific systems being investigated. In this paper, the potential noise fluctuations during the free corrosion of commercial aluminum alloy LY12 in sodium chloride solution was recorded and analyzed with different techniques. The typical results showed that the fractal dimension (D,n) obtained from spectral power density (SPD) is mainly directly proportional to the intensity of pitting corrosion and to the value of pitting parameter (SE) derived from dimensional analysis, while the fractal dimension (DE) obtained from EIS is mainly related to the uniform corrosion.展开更多
基金Projects(21073162,51131005)supported by the National Natural Science Foundation of ChinaProject(Y4100206)supported by the Science and Technology Bureau of Jiaxing Municipality and Zhejiang Provincial Natural Science Foundation of China
文摘The corrosion behaviors of copper and copper/titanium galvanic couple （GC） in seawater were studied by electrochemical impedance spectroscopy （EIS） and electrochemical noise （EN） techniques in conjunction with scanning electron microscopy （SEM） method. The results show that the corrosion process of copper in seawater can be divided into two stages, in which corrosion resistance and SE show the same evolution trend of initial increase and subsequent decrease, while SG changes oppositely. However, the ensemble corrosion process of copper/titanium GC in seawater includes three stages, in which corrosion resistance and SE show the evolution features of initial decrease with a subsequently increase, and the final decrease again;while SG changes oppositely. The potential difference between copper and titanium in their galvanic couple can accelerate the initiation of pitting corrosion of copper, and both the minimum and maximum corrosion potentials of copper/titanium GC are much more positive than those of pure copper.
基金Acknowledgements - The authors wish to acknowledge the financial support of the National Key Basic Research Foundation of China
文摘Spontaneous electrochemical noise (EN) can be a rich source of information concerning the processes simultaneously occurring on a corroding interface. But the noise signal is often difficult to be analyzed due to the complicated nature of the specific systems being investigated. In this paper, the potential noise fluctuations during the free corrosion of commercial aluminum alloy LY12 in sodium chloride solution was recorded and analyzed with different techniques. The typical results showed that the fractal dimension (D,n) obtained from spectral power density (SPD) is mainly directly proportional to the intensity of pitting corrosion and to the value of pitting parameter (SE) derived from dimensional analysis, while the fractal dimension (DE) obtained from EIS is mainly related to the uniform corrosion.
