According to the US Department of Defense, corrosion costs the Navy approximately US$7 billion every year. That's certainly an incentive for developing a method of keeping military vehicles from rusting. Now, researchers from the Office of Naval Research and The Johns Hopkins University Applied Physics Laboratory may be onto something. They're looking into the use a powder that could allow scratched or chipped paint to "heal like human skin."
The powder, known as polyfibroblast, consists of microscopic polymer spheres that contain an oily resin. Polyfibroblast can be added to paint primer, in order to completely cover the exterior surfaces of a vehicle. When the primer is scratched, the spheres in that area rupture, causing the resin that was inside of them to flow out. That resin forms a "waxy, water-repellant coating," that protects the exposed steel from the elements.
In a lab test, steel surfaces coated with the resin were able to resist rusting for up to six weeks, when kept in a chamber filled with salt fog.
If any of this sounds familiar, it's because other self-healing paints have already been developed, that also utilize spheres filled with liquid. While those are more concerned with maintaining the aesthetics of cars, however, the polyfibroblast primer is aimed squarely at protecting military vehicles in a variety of environments.
"We don’t care if it’s pretty," said Johns Hopkins' Dr. Jason Benkoski, lead scientist on the project. "We only care about preventing corrosion."
Source: Office of Naval Research