Yale researcher unlocks the complex code of microstructures
By Jim Shelton
08/16/13, 12:00 AM EDT
NEW HAVEN >> Jan Schroers and his colleagues are here to shatter some attitudes about glass.
While they’re at it, they’ll bend a few metals to their will.
“We can decode the complexity of materials,” said Schroers, a Yale University professor of mechanical engineering and materials science who has developed a technique that strengthens our understanding of an array of materials, from steel alloys to metallic glass.
The new technique involves “artificial microstructures.” Schroers and Yale colleague Baran Sarac co-authored a paper on the process in the journal Nature Communications.
Researchers have long sought a dependable way to gauge the relationship between a material’s internal structure and its physical properties, such as strength, flexibility and durability. Schroers likened it to the “holy grail of materials science,” something that could open up new realms of innovation for products large and small.
What if glass could be made stronger? What if nuclear power plants could stand up to greater stress? What if the aerospace industry had additional materials at its disposal?
“These are things we can study in detail,” Schroers said, in a Skype interview from Switzerland. “Our tool box is now quite versatile.”
In one sense, Schroers explained, this is the study of imperfections.
The microstructure of glass, wood, metal and other materials is incredibly complex. It includes a host of variations, or imperfections, that relate to its physical properties. A change to any single imperfection, from the shape or grain size of the microstructure to its spacing or dispersion, can have dramatic and complicated effects on the other imperfections. And while computer modeling is reliable in some cases, it can be inaccurate in other instances.
Schroers is able to alter one variable in a microstructure and keep all others variables stable. He said he and his research group use a combination of two existing processes, silicon lithography and thermo plastic forming.
The work is funded by a number of sources, including the U.S. Department of Energy, the National Science Foundation and Yale’s Center for Research on Interface Structures and Phenomena.
Beyond the technological advances hinted at by artificial microstructures, Schroers said there are applications in other fields, as well. For example, scientists could use artificial microstructures to study materials in nature, from plant stems to animal bones.
“We can take a picture of these structures and be able to characterize them,” Schroers said. “Take bones. Nature doesn’t create the stiffest possible bones. It includes slight imperfections. It takes a compromise approach between the best flaw tolerance and the best performance. Nature considers this a much more robust solution.”
Call Jim Shelton at 203-789-5664.