Investigating The Corrosion Behavior of Electrodeposited Nickel-Nano Diamond Composite Coating On Porous Materials by The Cyclic Voltammetry Method

In this work, Intralube E with 0.38 % C press-ready mix powders were pressed with 550 MPa pressure and sintered 25 min at 1120 °C. Samples were coated electrochemically with nano diamond (ND) reinforced nickel to study the effect of nano composite coating on corrosion behavior by cyclic voltammetry method. The corrosion properties of uncoated, nickel-plated and samples coated with ND reinforcement at seven (0, 1, 1.5, 2.5, 5, 7.5, 10, 20 g/l) different concentrations were investigated. Corrosion resistance of these samples improved with the coating and with increasing ND content. The pitting formation decreased with the presence of ND. Breakdown potential increased from -210 mV to 30 mV, protection potential increased from -430 mV to 10 mV, passivation range increased from 0.97 mV to 1.25 mV, the current peaks on the anodic branches decreased from 53.89 mA to 0.42 mA, and lastly the difference between Eb and Ep decreased from 220 mV to 20 mV from uncoated to 20 g/l nano-diamond reinforced nickel coating. The less the difference, the less the susceptibility to corrosion. Decreasing current means increased corrosion resistance and improved passivation increases the corrosion resistance. Finally, Cl- ions were observed on the corroded surfaces with the EDS and SEM analyses.