Compound Interest

Waterproof Gortex, stick-resistant Teflon, and bulletproof Kevlar are just a few of the extremely useful materials common today that until quite recently were unknown. Remarkably, the rapidly developing field known as materials science, which has already made significant contributions in such important fields as medicine, computer technology, and telecommunications, is still in its infancy.
"It is a very 'hot' area of science," says Dave Johnson, director of the University of Oregon's Materials Science Institute, "in part because advances in our labs can find their way into the market in a very short time."
Johnson likes to explain his work in, well, concrete terms. "Construction engineers have known for a long time that concrete has great compressive strength and steel has great tensile strength. By combining the two materials in steel-reinforced concrete, they end up with a superior material that utilizes the best characteristics of both. We do a very similar thing on a molecular level." (see "Principal Research Interests".)
While reinforced concrete is useful for construction purposes, the techniques Johnson is developing could yield exotic new materials useful in many fields. For example, superhard materials could make better drill bits, industrial saws, or razor blades; materials that combine hardness and heat resistance could be used in superdurable jet engines.
"We are learning how to combine the desirable properties of material A and material B to make hybrid materials with combinations of hardness, slipperiness, resistance to acid, special electrical responses--all kinds of properties."
To make these materials, Johnson uses a sophisticated machine called an evaporation chamber. By vaporizing material at very high temperatures, then "letting the dust settle," the machine lays down extremely thin layers--often only one atom thick--of individual materials one on top of another, like layers of different-colored paint. The materials can then be made to combine into new supercompounds.

One of the compounds Johnson is investigating has "thermoelectric" properties; that is, a flow of electricity makes the material cool at one end and hot at the other. This property can be exploited in various ways: power generation from waste heat, air conditioners, or small refrigerators--even a "cooling chip" for personal computers and other microelectronic devices where heat buildup is a problem. Using old methods only a few thermoelectric materials could be produced, but Johnson's lab has devised trail-blazing techniques to produce numerous new thermoelectric compounds with the potential for enhanced performance. Several manufacturers are working with the lab to explore the commercial potential of these new materials.
In the mid 1980s the Oregon Centers of Excellence program, instituted by the Oregon Legislative Assembly to promote the state's economic future, provided the university with funds to create the Materials Science Institute. Johnson, then working as a senior scientist for the DuPont corporation, was one of the first researchers hired. Since then, the institute has blossomed, growing to fourteen faculty members and between forty and fifty graduate students.
"Our work feeds the developing Oregon economy with highly skilled individuals," Johnson says. "Our students get the best of both worlds: a big research university's facilities and top professors, but small classes and the opportunity--even as undergraduates--to work in a research lab." In addition, he notes, beginning next year, the institute's graduate students will be able to apply for six- to nine-month internships with some of Oregon's leading high-tech corporations.

Back to INQUIRY, Fall 1997