Improving the Corrosion Resistance of Bronze (G-CUSN10) by Coating It with Graphene Oxide and Reduced Graphene Oxide Using Electrochemical Deposition Technology

This research aims to deposit a coating layer of Graphene oxide and reduced Graphene oxide on a substrate of bronze metal (G-CUSN10), which is one of the most widely used bronze alloys in the manufacture of centrifugal water pump impellers.

The deposition process was carried out using electrophoretic deposition technique by applying a constant voltage of 10 volts for 15 minutes. The carrier medium was distilled water, 0.03% Graphene oxide, and the same percentage of reduced Graphene oxide manufactured using the modified Hummer's method.

The coating layer was verified using different techniques: (scanning electron microscope, X-ray diffraction device, and Raman spectrometer), These tests confirmed that the coating layer conforms to the reference properties of Graphene oxide.

Then the corrosion of a sample coated with Graphene oxide, another coated with reduced Graphene oxide, and another without covering, was studied using a Tafel device in an aqueous solution containing 3.5% sodium hypochloride at a temperature of 25 degrees Celsius, where the corrosion voltage value for the open circuit of the bare sample was (-291 mv). The value of the corrosion current was (12.552 μA/cm2), and the voltage for the sample covered with Graphene oxide was (-250 mv) and the corrosion current was (1.990μA/cm2). As for the sample covered with reduced Graphene oxide, the voltage was( -210 mv) and the corrosion current was

(0.125 μA. /cm2).

From these values it is clear that Graphene oxide has significantly reduced the corrosion current, which reduced the corrosion rate by (84.1%). The same is true for the sample covered with reduced Graphene oxide, which reduced corrosion by (99%).

This research showed the importance of covering with Graphene oxide in increasing the corrosion resistance of bronze (CUSN10) in a medium containing sodium hypochloride used in sterilizing drinking water. This increase in corrosion resistance will increase the life of the impellers used in drinking water pumps, which maintains their work efficiency.