Researchers at Brookhaven National Laboratory have developed an all-in-one experimental setup at the National Synchrotron Light Source II that allows four different CT techniques to be performed on the same experimental sample, streamlining the characterization of complex fuels and reactor components across multiple size scales.
Unifying CT Techniques for Nuclear Materials
As global energy demand continues to rise, driven in part by artificial intelligence, researchers are looking to nuclear energy to provide reliable around-the-clock power. However, building the next generation of nuclear reactors requires a deep understanding of how nuclear fuel, reactor components, and storage technologies hold up against radiation, corrosion, high temperatures, and mechanical stress.
“Nuclear reactors are designed to operate for several decades, but we cannot wait that long to understand how materials will hold up in extreme nuclear environments.”
Mehmet Topsakal, materials scientist in the Nuclear Science and Security Department at the U.S. Department of Energy’s Brookhaven National Laboratory, via azom.com
Traditionally, scientists study these challenges using high-energy X-rays and computed tomography (CT) to build 3D pictures of a material’s internal structure without destroying it. Yet, much like medical patients needing an MRI, blood work, and genetic sequencing at different locations, researchers previously had to conduct multiple separate CT experiments to fully evaluate a single sample. To solve this fragmentation, researchers at Brookhaven National Laboratory developed a single experimental setup where four different CT techniques can be performed on the same experimental sample.
Inside the X-ray Powder Diffraction Beamline Setup
The new experimental rig is housed at the X-ray Powder Diffraction beamline of the National Synchrotron Light Source II (NSLS-II), a Department of Energy Office of Science user facility. The technical achievement and a demonstration of the new capability were published in the Journal of Synchrotron Radiation. The system was commissioned through a collaboration involving the DOE Office of Nuclear Energy’s Nuclear Science User Facilities program, Brookhaven Lab’s Nuclear Science and Security Department, and NSLS-II itself.
“NSLS-II is one of a few facilities in the world for studying dense, high-atomic-number materials, like nuclear materials, using an all-in-one method.”
Sanjit Ghose, XPD’s lead beamline scientist and one of the paper’s corresponding authors, via azom.com
That capability stems from the XPD beamline’s generation of high-energy hard X-rays. These beams can penetrate heavy steels used in nuclear reactors and fuels containing actinides, such as radioactive uranium. Furthermore, the beamline can focus those hard X-rays down to a beam width of just 15 microns—about one-quarter the width of a human hair—giving researchers high spatial resolution.
Four Simultaneous Imaging Methods
By unifying four specific techniques into one workflow, the setup allows scientists to reveal a sample’s internal structure, chemical makeup, and physical shape all at once. This is particularly valuable for complex materials featuring both ordered and disordered regions.
- X-ray Absorption CT: Reveals physical structure, density variations, cracks, and voids using high-energy hard X-rays.
- X-ray Fluorescence CT: Maps chemical elements and their precise locations within the sample using the small beam.
- X-ray Diffraction CT: Probes the atomic-scale structure for organized, crystalline materials.
- Pair Distribution Function CT: Examines atomic arrangement for disordered, amorphous materials.
Operating these four techniques together yields a view of how radiation alters materials, introducing defects and redistributing chemical elements throughout the structure.
“By conducting these four techniques simultaneously, we can pinpoint exactly where those chemical changes occurred and connect them to how the material’s strength and brittleness have changed. That structure-composition-property relationship is what we want to understand when studying nuclear materials.”
Simerjeet Gill, deputy chair of Brookhaven’s Nuclear Science and Security Department, via azom.com
Broader Probing of Quantum and Advanced Materials
Beyond synchrotron-based setups, researchers are also looking toward ultra-fast dynamics using X-ray Free Electron Laser (XFEL) facilities. Quantum materials often exhibit novel and multifunctional properties due to strong coupling between lattice, charge, spin, and orbital degrees of freedom. When perturbed into an excited state, these materials generate non-equilibrium phases on a femtosecond timescale, including light-induced superconductivity and ultra-fast solid-phase structural transformations.
Facilities such as the European XFEL and the Linac Coherent Light Source provide ultra-short pulses of coherent X-rays. These sources make it possible to measure ultra-fast dynamics simultaneously with nanoscale spatial resolution and femtosecond time resolution. Projects aim to apply time-resolved Bragg coherent diffraction imaging to prototypical systems like bismuth ferrite and vanadium dioxide, seeking to directly observe atomic motions during quantum phase transitions and deepen the understanding of the physical processes.
