The influence of temperature, chloride ions and sulfide ions on the anticorrosion behavior of 316L stainless steel in simulated cooling water was studied by electrochemical impedance spectroscopy and anodic polarizati...The influence of temperature, chloride ions and sulfide ions on the anticorrosion behavior of 316L stainless steel in simulated cooling water was studied by electrochemical impedance spectroscopy and anodic polarization curves. The results show that the film resistance increases with the solution temperature but decreases after 8 days’ immersion, which indicates that the film formed at higher temperature has inferior anticorrosion behavior; Chloride ions and sulfide ions have remarkable effects on the electrochemical property of 316L stainless steel in simulated cooling water and the pitting potential declines with the concentration of chloride ions; the passivation current has no obvious effect; the rise of the concentration of sulfide ions obviously increases the passivation current, but the pitting potential changes little, which indicates that the two types of ions may have different effects on destructing passive film of stainless steel. The critical concentration of chloride ions causing anodic potential curve’s change in simulated cooling water is 250 mg/L for 316 L stainless. The effect of sulfide ions on the corrosion resistance behavior of stainless steel is increasing the passivation current density Ip. The addition of 6 mg/L sulfide ions to the solution makes Ip of 316 L increase by 0.5 times.展开更多
The effect of Cl^- on the 316L stainless steel in simulated cooling water has been studied using polarization curves, electrochemical impedance spectroscopy (EIS), Mott- Schottky plot and scanning electron microsco...The effect of Cl^- on the 316L stainless steel in simulated cooling water has been studied using polarization curves, electrochemical impedance spectroscopy (EIS), Mott- Schottky plot and scanning electron microscopy (SEM) techniques. Cl^- concentrations vary from 200 to 900 mg/L. Results reveal that the corrosion resistance increases with the decrease of Cl^- concentration in simulated cooling water. The increase of Cl^- concentration leads to the shift of the corrosion potential towards the positive direction. Mott-Schottky curves show that in the passive film, Cr2Oa and FeO at the inner layer exhibit P-type but Fe2O3 and CrOa (CrO4^2-) N-type semiconductive properties. The SEM/EDX data demonstrate that elements such as Fe, O, C, Si and Cl as well as the presence of calcium and aluminum are presented on the surface of the metal.展开更多
文摘The influence of temperature, chloride ions and sulfide ions on the anticorrosion behavior of 316L stainless steel in simulated cooling water was studied by electrochemical impedance spectroscopy and anodic polarization curves. The results show that the film resistance increases with the solution temperature but decreases after 8 days’ immersion, which indicates that the film formed at higher temperature has inferior anticorrosion behavior; Chloride ions and sulfide ions have remarkable effects on the electrochemical property of 316L stainless steel in simulated cooling water and the pitting potential declines with the concentration of chloride ions; the passivation current has no obvious effect; the rise of the concentration of sulfide ions obviously increases the passivation current, but the pitting potential changes little, which indicates that the two types of ions may have different effects on destructing passive film of stainless steel. The critical concentration of chloride ions causing anodic potential curve’s change in simulated cooling water is 250 mg/L for 316 L stainless. The effect of sulfide ions on the corrosion resistance behavior of stainless steel is increasing the passivation current density Ip. The addition of 6 mg/L sulfide ions to the solution makes Ip of 316 L increase by 0.5 times.
基金supported by the National Natural Science Foundation of China (No.50871020)Science & Technology Program of Beijing(No.D09030303790901)
文摘The effect of Cl^- on the 316L stainless steel in simulated cooling water has been studied using polarization curves, electrochemical impedance spectroscopy (EIS), Mott- Schottky plot and scanning electron microscopy (SEM) techniques. Cl^- concentrations vary from 200 to 900 mg/L. Results reveal that the corrosion resistance increases with the decrease of Cl^- concentration in simulated cooling water. The increase of Cl^- concentration leads to the shift of the corrosion potential towards the positive direction. Mott-Schottky curves show that in the passive film, Cr2Oa and FeO at the inner layer exhibit P-type but Fe2O3 and CrOa (CrO4^2-) N-type semiconductive properties. The SEM/EDX data demonstrate that elements such as Fe, O, C, Si and Cl as well as the presence of calcium and aluminum are presented on the surface of the metal.