| Nuclear Materials Research |
Materials Option
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Nuclear Materials
The progress of any technology depends on the performance of the materials it employs. Materials used in nuclear technology suffer from degradation due to radiation. The goal of the research on nuclear materials is to understand the effects of radiation and use the knowledge gained to improve materials resistance for applications in energy production or storage of radioactive materials. The changes that occur in materials by radiation can also be exploited to develop materials with special properties that cannot be achieved by conventional methods of synthesis. This has opened up new areas of research involving the use of radiation effects and radiation-based techniques for materials synthesis and characterization.
Some examples of ongoing materials research:
Irradiation-Assisted Stress Corrosion Cracking of Austenitic Stainless Steels
This program is investigating the influence of irradiation on the stress corrosion cracking process in stainless steels used in nuclear reactor cores. High energy protons are used in place of neutrons to induce grain boundary segregation and microstructural changes, eliminating the problem of sample activation and reducing sample analysis time from years to months.
Materials for the Very High Temperature Gas Reactor
This experimental program addresses two of the materials challenges of the very high temperature gas reactor (VHTR). They are, oxidation of metallic components at temperatures up to 1000°C, and the irradiation-induced creep that will occur in the TRISO fuel particles. Understanding these phenomena is critical to the development of materials that can operate in very high temperature environments.
Behavior of Irradiated Materials in Supercritical Water
This program is focused on the behavior of materials in supercritical water, relevant to the supercritical water reactor. However, little is know about the behavior of materials in both the unirradiated and irradiated conditions. Materials irradiated with accelerator-produced ions and in reactor cores are studied and facilities to test neutron-irradiated materials have been built for that purpose.
Radiation Induced Amorphization in Ceramics and Minerals
This program addresses fundamental issues in particle-solid interactions for structurally and compositionally complex ceramics. The effects of structural topology, bond-type, dose rate, and irradiation temperature on the final state of the irradiated material are investigated.
Radiation processing of novel patterned nanostructures
Energetic electron and ion beams are utilized to process 2-D and 3-D nanostructures in the surface region of metals, semiconductors and ceramics. These nanostructures include 3-D nano-scale void lattice and nanofibers arranged in micro-scale patterns that may have unique optical properties for potential applications in advanced micro- and nano-devices. The fundamental mechanisms for the formation of these nanostructures involve radiation stimulated self-organization processes. Both experiments and theoretical modeling/simulation are undertaken to fully understand these processes.
Deformation and structural transformations in metallic glasses
Metallic glasses are metal alloys that do not exhibit crystalline order. They have high strength and can store large amounts of elastic energy. However, their plastic deformation is localized to nanometer-sized shear bands, making them macroscopically brittle. A challenge to practical applications of metallic glasses is to prevent their catastrophic failure along shear bands. The goal of current research is to gain an improved understanding of the structure, mechanical behavior and modification of shear bands, using a combination of experimental techniques and modeling.
Materials Faculty:
Gary S. Was, Michael Atzmon, Lumin Wang
Adjunct/Joint Faculty:
Rodney Ewing, Sebastien Teysseyre, Jeremy Busby
Materials Labs:
