Thursday, September 17, 2009

U.Va. Center Looks to Mitigate Problems of Corrosion of Engineered Materials

September 16, 2009 – UVA Today by Fariss Samarrai

Everywhere John Scully looks, he sees corrosion, or materials that will corrode. Corrosion is his specialty. His mission is to mitigate it.

Scully is the Charles Henderson Professor of Materials Science and Engineering in the School of Engineering and Applied Science and co-director of U.Va.'s Center for Electrochemical Science and Engineering.

The center – along with the materials science department – trains engineering students in ways to limit corrosion of the materials they are likely to work with, designs corrosion-resistant materials and provides expertise to government and companies looking for solutions to corrosion problems.

Historically, corrosion has meant rust, or the destructive oxidation of metals. But it also applies to an amazing array of nonmetallic materials. It involves the degradation and loss of function of materials to combinations of factors, such as moisture, heat, cold and physical stress.

Airframes crack, bridges weaken and electronic devices go haywire.The nation's infrastructure is degrading as old structures lose their vitality to the effects of age. The costs for maintenance, repair, replacement and disposal are highly significant, involving everything from transportation to weapon systems to health care products. Approximately $300 billion is spent each year in the U.S. to fix or replace things that break down due to corrosion.

"From the Bronze Age to the Industrial Age, there has been a prolific expansion in the number of engineered materials that humans have created for our everyday use," Scully said. "And we are in the midst of a materials revolution as ever more materials are being engineered, some at the nanoscale, others with little margin for safety to save weight and energy costs, for instance. But as we make new materials we also are coming to an end of the age of the 'disposable society.'"

What we make must endure, Scully said, whether it be renewable batteries for cars or laptops, or the infrastructure for sustainable sources of energy. This is because of shortages of certain materials as well as the high energy cost and the carbon footprint associated with processing raw materials into engineered components.

And some materials may need to last for extremely long periods of time, such as the casing materials used for nuclear waste storage, which must remain intact for 10,000 years or more. Scully says that the degradation of engineered materials, such as metals, polymers, paints and nanoparticles, is not only a threat to safety and to the economy, but may be a barrier to future technological advances, such as rechargeable batteries and fuel cells.

"The costs of corrosion to our health and safety is becoming increasingly dependent on our ability to make materials last much longer and to function at optimal levels," he said.

Last year Scully served on a National Academies of Science committee that assessed corrosion education in engineering schools across the nation and reported earlier this year that most are not putting enough curricular emphasis on training students in issues involving corrosion, and on ways to mitigate these problems.

"As a nation, we really need to revitalize corrosion education in the nation's workforce and engineering research community," Scully said. "In the long run, this will pay great dividends in savings, safety and preparedness as well as help enable things like energy independence."

U.Va. takes the issue seriously and has one of the most vibrant corrosion education programs in the country, Scully said. In addition to providing courses for undergraduate students, the Engineering School provides extensive corrosion training at the graduate level and for industry and government. Scully's center also conducts corrosion research on materials for companies, synthesizes its own materials and coatings and even provides "life-prediction" analysis of the potential long-term effects of corrosion.

"Corrosion of metals increases costs to all industries due to losses of efficiency, loss of product and operational downtime," Scully said. "Many companies lack in-house corrosion expertise or enough staff to handle this aspect of their engineering needs, so many come to us for help solving their corrosion issues and problems."

The center also conducts research on environment-assisted fracture in a range of materials, looking for ways to mitigate or nearly eliminate these common problems.

This year the center was recognized with the 2009 Distinguished Organization Award from the National Association of Chemical Engineers.

At a Department of Defense-sponsored corrosion conference in Washington last month, four U.Va. students won first- and second-place awards in technical poster sessions for corrosion engineering, modeling of corrosion and corrosion science.

"Corrosion is not going to go away," Scully said. "But through our research and training efforts, we can greatly slow that process of degradation and help society achieve many of the technological goals that we face in the 21st century."