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February 2012 Previous month Next month

Neil Young, one of my favorite rock musicians ever, said it best in his 1979 album by the same name: Rust Never Sleeps.


Have you ever tried to get rust off of the underbody of your car? I have. Multiple times. I’ve used the rust-killer spray, and then I’ve used the rust-resistant paint to cover it up. It looks good for a while, but it always comes back. Always.


Fortunately, I have never had more than a touch of rust on a couple of cars I have had for many years because we in the Washington, D.C., area don’t get a lot of snow and ice. This winter we have recorded less than an inch of snow. Rust isn’t a huge problem for us. But I wonder about people who live in the colder climates where their poor vehicles are bombarded with a road-spray mixture of salt and chemicals for months.


So it is with pleasure that I call your attention to a noteworthy PressPac item this week.

New research has established the “miracle material” called graphene as the world’s thinnest known coating for protecting metals against corrosion. A study on this potential new use of graphene appears in ACS Nano. While the technique is not being applied to car and truck metals, it does include aircraft components, and overall this is an encouraging development in the fight against corrosion.

In the study, Dhiraj Prasai and colleagues point out that rusting and other corrosion of metals is a serious global problem, and intense efforts are underway to find new ways to slow or prevent it. Corrosion results from contact of the metal’s surface with air, water or other substances. One major approach involves coating metals with materials that shield the metal surface, but currently used materials have limitations. The scientists decided to evaluate graphene as a new coating.

Graphene is a single layer of carbon atoms, many layers of which are in lead pencils and charcoal, and is the thinnest, strongest known material. That’s why it is called the miracle material. In graphene, the carbon atoms are arranged like a chicken-wire fence in a layer so thin that is transparent, and an ounce would cover 28 football fields.

They found that graphene, whether made directly on copper or nickel or transferred onto another metal, provides protection against corrosion. Copper coated by growing a single layer of graphene through chemical vapor deposition (CVD) corroded seven times slower than bare copper, and nickel coated by growing multiple layers of graphene corroded 20 times slower than bare nickel. Remarkably, a single layer of graphene provides the same corrosion protection as conventional organic coatings that are more than five times thicker. Graphene coatings could be ideal corrosion-inhibiting coatings in applications where a thin coating is favorable, such as microelectronic components (e.g., interconnects, aircraft components and implantable devices), say the scientists.

 

Read more about this amazing development.

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