University of Michigan researchers have discovered that metal alloys with three or more elements in equal concentrations can be remarkably resistant to radiation-induced swelling, in findings that could change the way industries like nuclear energy and aerospace look for materials that can stand up to radiation exposure.
The big problem faced by metals bombarded with radiation at high temperatures—such as the metals that make up nuclear fuel cladding—is that they have a tendency to swell up significantly. They can even double in size.
Colleagues at Oak Ridge National Laboratory in Tennessee created samples of a variety of nickel-based alloys. These were then exposed to radiation in a facility at the University of Tennessee. The samples were analyzed at U-M’s Center for Material Characterization with a transmission electron microscope. The team found that compared to pure nickel, the best alloys had more than 100 times less radiation damage.
The team worked closely with the group of Fei Gao, a theoretician and U-M professor of nuclear engineering and radiological sciences. The work was supported as part of the Energy Dissipation to Defect Evolution Center, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences.
