The high temperature materials and nuclear fuels laboratory operates out of the Science and Engineering Research Facility (SERF) building on the campus of the University of Tennessee Knoxville (UTK). It is currently developing, investigating and prototyping ceramics and refractory materials for extreme environment applications, with a particular focus on synthesis, characterization and testing. Its current focus is on plasma facing materials for fusion extreme environments, blanket materials and concept development in uranium and hydride materials.
Currently, industry (proprietary) research programs are being conducted at the facility. These are sponsored at a variety of Technology Readiness Levels (TRLs) from 2-6. In particular, a section of the laboratory is currently an EX / CUI space with an active Technology Control Plan until 2028. [Photos: (left to right) Prismatic block concept demonstrating feasibility issues in core structures; XCT confirming TRISO kernel arrangements; student researcher examines their own 3D printed ceramic heat exchanger concepts.]
A variety of analytical approaches are used to ensure consistent synthesis and quality control. Metrology and quality control are a significant endeavor and used in both fundamental and applied research, prior to applying instrumental analysis techniques. In-lab monitoring includes radiation monitoring, feedback and thermocouples for temperature, standard solutions for liquids, gas pressure methods for vapors, gas and moisture sensor systems, and their supporting traceable NIST materials and calibration articles are present in the facility. This systematic approach recognizes the broad complexities of materials development, and the recognition that a change in a single detail has consequences on development downstream and upstream, with evolution from design, modeling and iterative testing. [Photos: (left to right) Isotope target, failure simulation and capsule design leading to fabrication of ceramic encapsulations.]
The facility also has a significant history and technical expertise in the process control and development of particle fuel compacts. In particular, the refinement of particle fuels encapsulated in a ceramic or graphite matrix was the original purpose of the laboratory. Such particles include surrogate kernels based on UC and UC2, as well as the traditional UO2 and UCO. Several variations of coatings have been experimented and tested in the facility with ceramics, include CVD pyrolytic carbon (OPyC, IPyC, buffer) as well as CVD ZrC and SiC. The laboratory is licensed for uranium processing, including high temperature heating that includes several engineering controls for radiological containment up to exhaust capture. [Photo: (left) Surrogate fuel particles with unique interfaces designed for inert matrix and composite fuel “cer-cer” concepts. (right) TRISO fuel compacts in SiC matrix.]
There are also undergraduates from the UT-Oak Ridge Innovation Institute, Department of Nuclear Engineering and the Department of Materials Science and Engineering either conducting their own research projects for the Center for Materials Processing (CMP) or enabling other programs. The laboratory hosts a score of graduate and undergraduate students, leading to research output focused on workforce development, and improved understanding of materials processing and properties. Students begin their foundation in the kinetics and chemical thermodynamics of materials science, and apply their knowledge toward understanding of the properties of nuclear materials. [Photo: condensed figures from Connor et al (now at TRISO-X) demonstrating a method to study densification kinetics of commercial zirconium carbide and the problematic role of oxygen]
The lab has systems for inventory, quality control, equipment training and safety program is overseen by the presence of both industry and university PIs. Finally, the laboratory recognizes and acknowledges the collaboration and dependency between research and facilities (SM, BA), information technology (BB, BE, RW), safety (SM, SD), administrative staff (AR, AN, AL, JH, MR) and their vital role in future-proofing infrastructure and capability. [Photo: Facilities, students and staff interface and plan laboratory upgrades]
Please direct any questions to [email protected] for further information.