Solving Energy Challenges One Grain Boundary at a Time

Solving Energy Challenges One Grain Boundary at a Time

Stephanie PittsBy Alyssa Patrick, CEA Intern

Stephanie Pitts, a mechanical engineering Ph.D. candidate and fellow with the Nuclear Energy University Programs (NEUP), is working to better understand and develop new materials for use in nuclear power plants.

Pressure and irradiation levels can cause voids and cracks in the structural metals inside nuclear power plants. Pitts is working with her advisor, Dr. Hussein Zbib, to create a computational model of how steel reacts to irradiation. As part of the Department of Energy, NEUP promotes research on nuclear energy security.

“I’m really interested in metal grain boundaries. Metals have different grains that are similar to rock candy crystals. The crystals in rock candy jut out at different angles, meaning they don’t line up perfectly with each other. The same thing happens in metals,” Pitts said. Those boundaries are one of the dominating features that can cause metal failure under irradiation and stress, she says.

She hopes that her model will help to prevent machine damage before it happens. Knowing the pressure at which a metal will crack will allow power plants to avoid those occurrences by running machines at lower pressures.

She also hopes to discover materials that could be used for the latest nuclear reactor concept scientists are developing. These reactors, called GenIV, would operate on a closed fuel cycle and use recycled nuclear fuel. They would be super efficient, potentially producing ten times the energy with the same amount of uranium.

“Currently there are only design concepts for these reactors because it is important to know what kind of material will be able to hold up for 15 to 30 or more years in those nuclear conditions,” Pitts said.

Pitts sees nuclear energy as an important, sustainable, and renewable energy.

“While the renewable energies most talked about now like wind and sun power are exciting, they are not very reliable. The wind doesn’t always blow and the sun doesn’t always shine. Nuclear energy is clean, has a low carbon imprint, and is stable source of baseload power,” Pitts said.

Pitts received a BS in Mechanical Engineering from WSU in 2009 and is a graduate of the Honors College.