Effect of Hydrodynamic Condition on the Electrochemical Behavior of Various Metals in 3.5 wt% NaCl Solution

Abstract

The electrochemical behaviors of various metals with and without diamond-like-carbon (DLC) coating in 3.5 wt% NaCl solution were investigated. The effect of hydrodynamic conditions was focused by employing a rotating disc electrode (RDE). The experimental results showed that each bare metal had a more positive corrosion potential and a higher corrosion rate due to enhanced oxygen transport at the higher rotating speed of the RDE. DLC coating caused a substantial increase in the corrosion resistance of all metals studied. However, localized corrosion was still found in the DLC-coated metal at sites where deposition defects existed. Surface morphology examination was performed after the electrochemical test to confirm the roles of hydrodynamic conditions and DLC coating.

HARDNESS AND CORROSION BEHAVIOR OF Ti-20Cu-20Ni-20Mn- 20Zn AS HIGH ENTROPY ALLOY AND TI-13Cu-9Ni-5Mn-5Zn FOR MARINE STRUCTURE APPLICATION

“…The OCP determination time was chosen because the average OCP had a stable value with a deviation of less than 5% from t = 0 s to t = 120 s. The stability of the average OCP value indicates that the TiO2 film on the titanium surface is growing slowly and that the titanium surface is stable. The OCP stability as a function of time in titanium alloys in 3.5% NaCl solution has also been reported [16]. The EIS was performed with a frequency range of 100 kHz -0.05 Hz and an amplitude of 10 mV about OCP.…”