Erosion-corrosion Behavior Of Of Copper In Artificial Seawater

The erosion-corrosion behavior of copper in flowing seawater was studied withimpingement jet loop system. Erosion-corrosion behavior in different velocities （0m/s,3m/s,6m/s,7m/s） and impact angles （0°,30°,45°,60°,90°） artificial seawater, immersioncorrosion behavior in a long time and Erosion-corrosion behavior of copper after they haveproduced film, were investigated by Electrochemical Impedance Spectroscopy （EIS），Electrochemical Noise （EN）, Scanning Electron Microscopy（SEM）, on an impingement jetsystem.The influence of different erosion corrosion parameters on copper erosion corrosion, theimpedance at different flow velocities are less than copper static soak; Noise resistancereciproca(lR_n^-1)increase gradually along with the increase of the scouring velocity in certainerosion angle, which can declare that electrochemical corrosion rate increases with theincrease of the scouring velocity; R_n^-1and PSD curve white noise level increase graduallyalong with the increase of the erosion angle at3m/s and6m/s, which can declare adequatelythat electrochemical corrosion rate increases with the increase of the erosion angle. At thesame time, copper surface gradually transform from local corrosion into uniform corrosion;R_n^-1and PSD white noise level decrease gradually along with the increase of the erosion angleat7m/s. This can declare that electrochemical corrosion rate decreases with the increase of theerosion angle. At the same time, copper surface gradually transform from local corrosion intouniform corrosion; R_n^-1decreases gradually along with the elongation of erosion corrosiontime in certain erosion angle and at certain flow velocities, which declares thatelectrochemical corrosion rate increases with the elongation of erosion corrosion time. Fromthe velocity-impingement angle and R_n^-1three-dimensional diagram with the flushing time,we can see that the surface corrosion product film of copper is easy to build in the conditionof low velocity and low erosion angle, and the electrochemical corrosion rate decreasedgradually. But the film of copper growth is extremely difficult at the conditions of lowvelocity high erosion angle.With the increase of soak time, the impedance of copper increases gradually and thenreduces to keep in a certain range. Potential noise and current noise alternating by syntheticand incongruous change, which declares that the copper surface conduct the passivation film rupture/repair process （Metastable pitting growth and disappear）.At the same timeR_n^-1decreases and then keep in a certain range, which is consistent with the result of theelectrochemical impedance. With the increase of soak time, copper surface passivation filmgenerated and then gradually to dense, With copper in artificial seawater immersion timeincreases, the content of copper surface gradually reduce, oxygen content increased first, thendecreased. Other elements increase for500hours. And than, the study on copper erosioncorrosion behavior after long term soaking film in artificial seawater: The soaking film aftererosion corrosion in the flow seawater was broken down to some extent. Some places evenbare the matrix, but it has certain protective effect on the whole.