"A fusion reactor works by introducing plasma a hot, electrically charged gas that serves as the reactor fuel into a vacuum vessel," Wirth said. "The plasma is then confined using electric and magnetic fields into a central, vacuum region."
The problem, he said, is that ions from the plasma escape and bombard the material surfaces, in addition to the high-energy neutrons. This combination causes significant damage and changes the properties of the reactor materials.
"It's likely materials do not exist today that could be used to build a reactor that would contain the plasma," Wirth said.
The material property changes are driven by many processes that occur in less than a nanosecond. Yet, it is the cumulative interaction of such processes over much longer times that determine the precise value of these changes. Wirth and his team aim to develop models which stretch this interaction over the period of many decades to evaluate their long-term effects.
"We are trying to identify and model numerous microscale defect and impurity interaction processes that occur over rapid time scales which can span less than a nanosecond," Wirth said. "And then we are trying to integrate these into a model that can predict the material response over the years and decades for which a plasma reactor needs to operate."
Wirth notes that making these goals more challenging is the fact that no current experimental facilities exist that accurately represent the environment these materials are expected to face.
"Our research will address one critically important aspect toward getting to fusion energy," Wirth said. "I'm optimistic about the potential for fusion energy, but realistic in
|Contact: Whitney Heins|
University of Tennessee at Knoxville