By Charlie Feigenoff

Rust never sleeps—which is why it is so expensive. According to a study commissioned by the Federal Highway Administration, corrosion damage costs the U.S. economy $276 billion every year.

If John Scully has his way, rust will soon be sleeping—and sleeping soundly. Thanks to a productive collaboration with two other University of Virginia scientists, Scully has hit the trifecta of corrosion resistance—a full-featured protective coating that acts as a barrier, provides a sacrificial anode, and automatically releases corrosion inhibitors as they are needed. This new class of coatings has the potential to dramatically reduce the nation's infrastructure costs, lessening the need for routine maintenance, repair, and replacement.

Scully's coating-which combines aluminum, cobalt, and cerium-is designed to release inhibitors in response to the symptomatic change in pH associated with corrosion. "In essence, we've produced a smart coating that will provide protection only when it's needed," Scully remarks. "That makes them particularly long-lasting and efficient."

These new coatings are the product of pioneering research in a new class of materials-glassy metals-by Scully's colleagues, Joseph Poon and Gary Shiflet. Because glassy metals lack the crystalline structure of ordinary alloys, it is possible for metallurgists to fine-tune their properties for specific applications. As a result, Poon and Shiflet were able to synthesize the alloy for Scully that provides the precise protective qualities he requested.

These qualities could be adjusted further for other uses. "Glassy metal coatings might be used on stents," Scully says, "where they could be used to deliver desirable ions into the body on demand." He also envisions a coating that would release copper ions. Used on plumbing fixtures in hospitals, it could kill e.coli and other dangerous bacteria.

Scully is a professor in the U.Va. School of Engineering and Applied Science Department of Materials Science and Engineering and co-director of the U.Va. Center for Electrochemical Science and Engineering. He holds degrees in Material Science and Engineering from John Hopkins University.

Funding for the various aspects of Scully's research comes from a combination of sources: the federal government (NSF, ONR, NASA, AFOSR, DOE), specific federal laboratories (Sandia National Labs), industry (Alcoa, DuPont, Reynolds, GE, Newport News Shipbuilding, Copper Development Assoc.) and, on occasion, state agencies (VDOT).