MAE assistant professor Maschmann earns Oak Ridge Associated Universities award
Carbon nanotubes (CNTs) are infinitesimal tubular structures made of graphite that can be functionalized for different uses depending on their structure. They are one of the strongest known materials and may be added to composite materials to increase the strength of such things as bike frames, boat hulls and golf shafts.
Matt Maschmann, assistant professor of mechanical and aerospace engineering, recently was awarded a $5,000 Ralph E. Powe Junior Faculty Enhancement Award from the Oak Ridge Associated Universities to look into potential mechanical and electrical responses of carbon nanotubes grown directly on structural microfibers. MU is one of 114 Oak Ridge Associated Universities, and Maschmann’s proposal was one of only 35 funded.
“Carbon fibers are reasonably conductive, but when integrated into polymer matrix composites, the material system loses conductivity when embedded fibers are not in contact with each other,” Maschmann said.
The researcher worked with CNTs during his four years as a contractor in a U.S. Air Force research lab where some applications were inspired by the airflow sensing capabilities of flying insects.
“We used CNT-coated microfibers embedded within glass capillary tubes having electrodes on the top and bottom to work as hair sensors,” Maschmann said. “The final sensors look like hair plugs.”
When grown as an array, CNTs looks like a “fuzzy” coating on the glass fiber and that configuration increases conductivity.
“Small-scale compression of the fuzzy CNT layer creates a large electrical resistance change or response. I am looking at diverse coatings and the relationship of the coating to electrical responses,” Maschmann said.
As an example of the technology, he noted that Brian Wardle, a researcher at MIT, has adapted the technology to de-ice planes. “Current through the CNT layer generates heat,” he said.
Maschmann’s focus is electromechanical deflection.
“The technology may be utilized in various sensing modalities,” he said. “For example, internal damage to a composite material may be sensed by electrical resistance change of embedded CNT-coated fibers.
“The system response is highly sensitive to small changes in the CNT array coating,” Maschmann added. “I am trying to grow some optimum structure for optimum sensitivity. Our approach is to test the response of individual fibers by compressing the CNT coating by as little as a few nanometers, or billionths of a meter.”
“Matt Maschmann is exactly the type of outstanding young faculty member the Powe award seeks to recognize,” said Mechanical and Aerospace Engineering Department Chair Yuwen Zhang, who wrote a nomination letter for the award. “This project is a good fit for the educational and research goals of our department and his innovative approach is expected to provide significant insights. Matt also serves as an excellent role model to our undergraduate students.”
Maschmann’s research examines many aspects of nanoscale material synthesis and application, with an emphasis on carbon nanotubes. “The potential application space for CNTs is immense. IBM recently announced plans for CNTs to replace silicon transistors in computer processors by the year 2020.”
Some applications might be more science fiction. “There has been discussion for years to create a space elevator from spun CNT cables,” he said, smiling.