A Melbourne researcher has found ways to utilise graphene to coat mild steel, protecting it from corrosion and overcoming a technical barrier which has prevented successful coating of the ubiquitious metal.
Lecturer in the School of Vocational Engineering, RMIT Dr Sanjid Ahmed Patwary found in the study he led that graphene coatings dposited by chemical vapor deposition (CVD) could be manufactured with unique characteristics as barriers against aggressive environment.
Until now, because of some compelling technical reasons, it has been a nontrivial challenge to develop graphene coatings on the most commonly used engineering alloy, according to the paper Remarkably Corrosion Resistant Graphene Coating on Steel Enabled Through Metallurgical Tailoring, just published in the journal nano/micro Small.
Dr Patwary, who was a PhD research candidate at Monash University, Melbourne, first tested electroplating mild steel with a nickel layer, before applying graphene.
The paper concluded: “However, this approach proved too simplistic and does not work.
“This necessitated an innovative surface modification of MS (based on basic metallurgical principles) that enabled successful CVD of graphene coating on mild steel.”
The successful method involved depositing thin dual layers of copper and nickel of optimised thicknesses, according to the paper. Graphene was then deposited using chemical vapor deposition.
The researchers immersed that coated mild steel in a salt solution where it remained for more than 1,000 hours and was resistant to signs of corrosion.
“There is a clear trend for the resistance to be possibly everlasting.
“The optimised surface modification that enabled development of CVD graphene coating on mild steel is generic in nature, and it should enable graphene coating on other alloy systems, which would otherwise not be possible.”
Picture: Dr Sanjid Ahmed Patwary