Salt is a complicated molecule. It can make bland food more palatable and even melt hazardous ice on roads. However, the same salt that makes roads safer for driving, if not removed promptly, can cause major issues for the vehicles that drive through it. Over time, brine kicked up from the road onto the car can corrode and rust the metal parts, ruining engines and destroying paint jobs.
The same can be said for the metals within molten salt reactors and concentrating solar power plants. Molten salt reactors are a type of nuclear reactor using salts as either a coolant or fuel, and concentrating solar power plants use liquid salts as a heat transfer and storage medium. A major area of research involves the effectiveness of different materials within the reactors, especially those coming into contact with salts.
Claudia Rawn, associate professor of materials science and director of the Center for Materials Processing, and her JDRD team are investigating the effects of these salts on chromium-containing alloys in conjunction with Stephen Raiman, research associate in corrosion science at ORNL.
“Our colleagues at Oak Ridge are studying the chromium in structural materials that are in contact with molten salts in places including concentrated solar or nuclear reactors,” said Rawn. “The molten salt is in contact with different structural components and there is concern about the chromium leaching out into the salt.”
Rawn’s team plans to complement the work at ORNL by using X-ray diffraction to study the effects of these salts on structural materials that contain chromium. Raiman’s team will be investigating the interactions between molten salts and chromium in structural alloys, while Rawn will look at the salt itself.
In order to take an atomic look at the salts, Rawn’s team will use the recently established diffraction facility at the UT-ORNL Joint Institute for Advanced Materials. She hopes their work will provide an important piece of the molten salt–chromium interaction puzzle and serve as a stepping stone to future collaborations.