Drawing on their leadership in materials simulation and design, advanced microscopy and materials fabrication, University of Wisconsin-Madison engineers have developed a method for tuning the radiation resistance of high-entropy carbides. This new class of advanced ceramic materials has applications in fusion and next-generation fission reactors, as well as other high-temperature and extreme environments.
The interdisciplinary project was led by Izabela Szlufarska, a professor of materials science and engineering at UW-Madison, and included contributions from colleagues John Perepezko, Paul Voyles, Kumar Sridharan and Xudong Wang and their students. The paper appears in the Feb. 4, 2026, issue of the journal Nature Communications.
“These high-entropy carbides have very high melting temperatures, so they are ideal for applications like fusion, fission and inside turbines,” says Szlufarska. “Optimizing these materials is a really important next step.”
High-entropy metal alloys were first discovered about 20 years ago. Then, researchers began mixing equal parts of five or more metals together—in stark contrast to the traditional metal alloy composition of one base material augmented with a small percentage of one or two other materials. The result was stronger, more heat-resistant alloys with a broader range of interesting and surprising properties.
Since then, researchers have applied similar concepts to other materials, creating high-entropy oxides and high-entropy carbides, a type of ceramic that combines carbon with metals or metalloids. These materials, however, are so new and complex that researchers are still investigating their fundamental structures and properties.
That’s why the UW-Madison team decided to look for a characteristic called “chemical short-range order” in high-entropy carbides. This important feature of high-entropy metals was not readily apparent in the ceramics.
Many of the properties and the complexity of high-entropy materials are due to their mixture of many types of constituent atoms in an almost random arrangement. But when researchers looked at high-entropy alloys at the atomic level, they found that, in many cases, certain types of atoms tended to gravitate toward one another, not necessarily creating a regular structure, but a “neighborhood” of similar atoms. This phenomenon, called chemical short-range order, has many implications for designing and optimizing high-entropy alloys.
When they began their study, it was unclear to the researchers if the same short-range order existed in high-entropy carbides. “This is a very hard thing to confirm because experimentally you can’t just see individual atoms,” says Szlufarska. “So we studied it in two ways: We created atomistic simulations of these materials, and then we fabricated high-entropy carbides and conducted high-resolution microscopy to find the signals for these things.”
Both were difficult tasks; the simulation effort involved creating a powerful machine-learning potential—a type of atomic-level simulation—that could accurately represent the complexity of these materials. The simulation predicted that short-range order should exist in these ceramics, mediated by heat.
Guided by this information, the team then synthesized batches of high-entropy carbide materials. Voyles, a microscopy expert, and his students developed tools to sift through the various signals to identify any signs of short-range order in the material. In the end, the scans confirmed the first signs of short-range order.
Next, the researchers looked at whether they could control the prevalence of short-range order in the ceramics by altering their chemical composition and treating them with heat. They found that it was possible to ramp short-range ordering up and down through these treatments. Even more exciting, samples with greater chemical short-range ordering demonstrated increased radiation resistance. “It’s very promising and provides a new tool for optimizing radiation resistance in these materials,” says Szlufarska.
Now, the team is drilling down on exactly why short-range ordering in high-entropy carbides leads to radiation resistance. The researchers also plan to synthesize additional variations of the ceramics and study them to develop general rules about defect development and movement in the carbide materials, which are proving to be very different from high-entropy metals.
The team also anticipates working closely with other researchers throughout the College of Engineering and UW-Madison, where many additional researchers study high-entropy metal alloys or search for materials for use in high-temperature and high-radiation applications and extreme environments.
“There’s a significant focus on these complex materials at Wisconsin, which is exciting because we’re working together and there are a lot of synergies,” says Szlufarska. “I think you’re going to see a lot more projects and news coming soon.”
Top image caption: A representation of the atomic structure of a high-entropy carbide, which combines five different components with carbon.
Izabela Szlufarska is a Harvey D. Spangler Professor and chair of the Department of Materials Science and Engineering; John Perepezko is the IBM Bascom Professor; Paul Voyles is a Harvey D. Spangler Professor; Kumar Sridharan is a Grainger Professor and Vilas Distinguished Achievement Professor; Xudong Wang is the Thomas and Suzanne Werner Professor. Other UW-Madison authors include Shuguang Wei, Muhammad Waqas Qureshi, Jingrui Wei, Longfei Liu, Xuanxin Hu, Siamak Attarian, and Evan Willing. Other authors include Jianqi Xi of the University of Illinois; Ranran Su of Shanghai Jiao Tong University in Shanghai, China; and Hongliang Zhang of Fudan University, Shanghai, China.
The authors acknowledge support from the Department of Energy Basic Energy Science Program, Grant # DEFG02–08ER46493; The National Science Foundation OAC-1931298; and TG-MAT240078, from the Advanced Cyberinfrastructure Coordination Ecosystem: Services & Support (ACCESS) program, supported by National Science Foundation grants #2138259, #2138286, #2138307, #2137603, and #2138296.