Corrosion Control of Steel Rebars Using Electroless Nickel Coating

Due to rebar corrosion problem, more than the cost of construction is being spent towards repairs and renovation of concrete structures. If rebar corrosion problem continues, lifeline structures are subjected to sudden collapse. In order to keep away from the catastrophic failures, some effective additional protective measures must be undertaken in the construction stage itself. The objective in the present investigation is to modify the surface of the rebar by electroless nickel coating using three different thicknesses. The efficiency of the corrosion resistance properties of 10, 20, and 30 mu m coated steel was evaluated by conducting potential time studies test, and accelerated impressed voltage test. From the above tests conducted, it was found that the coated steel in potential time studies confirmed the stability of the coating even in the presence of aggressive chloride medium during 1 month exposure. 12 V accelerated impressed voltage test results indicated that the time taken for initial crack was doubled for 20 mu m coated steel.