To achieve energy security and clean energy objectives, the United States must develop and deploy clean, affordable, domestic energy sources as quickly as possible. Nuclear power will continue to be a key component of a portfolio of technologies that meets our energy goals. Nuclear Energy R&D activities are organized along four main R&D objectives that address challenges to expanding the use of nuclear power: (1) develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the life of current reactors; (2) enable the deployment of advanced reactors to help meet the Administration's energy security and clean energy goals; (3) develop sustainable nuclear fuel cycles; and (4) maintain US leadership in nuclear energy technology. To support these objectives, the Department of Energy is seeking to advance engineering materials for service in nuclear reactors. Please note: following award, all DOE SBIR/STTR grant projects requiring high performance computing support are eligible to apply to use the DOE National Energy Research Scientific Computing Center (NERSC) resources. NERSC is the primary scientific computing facility for the DOE. If you think you will need to use the computing capabilities of NERSC during your Phase I or Phase II project, you may be eligible for this free resource. Learn more about NERSC and how to apply for NERSC resources following the award of a Phase I or Phase II project at http://www.nersc.gov/users/accounts/allocations/request-form/. Grant applications are sought in the following subtopics: a. Bimetallic Structures for Liquid-Cooled, High Temperature Reactor Systems Advanced high temperature nuclear reactor systems may utilize liquid coolants to optimize heat transfer, neutronics, safety, and compactness of the nuclear supply system. Examples of such systems in which corrosion is a particular challenge are liquid-salt cooled reactors (both those in which the fuel is fixed and those where it is dissolved in the coolant) and lead- (or lead-bismuth) cooled reactors. In each of these reactors, the structural components of the primary systems in contact with the reactor coolant must be adequately compatible with the materials of the reactor components. While materials permitted for construction of high-temperature components of nuclear reactors are specified in Section III Division 5 of the ASME Boiler and Pressure Vessel Code, they may not provide adequate corrosion resistance with respect to the liquid coolants described for long corrosion lifetimes. One alternative is to develop bimetallic structures consisting of a corrosion-resistant surface layer (e.g., weld overlay cladding, roll bonding, etc.) and a structural substrate approved for use in ASME Code Sec III Div 5. Grant applications are sought to develop such a system with emphasis on fabrication methods (including for complex 3-D structures) and projected metallurgical stability over an extended component lifetime (> 20 years). Corrosion, aging, diffusion-related changes in composition, and thermo-mechanical loading should be considered. Note: Thin coatings will not be considered due to high likelihood of peeling, spalling, scratching, debonding, etc., over long component lifetimes. Questions Contact: Sue Lesica, sue.lesica@nuclear.energy.gov b. Powder Metallurgy-Hot Isostatic Pressing of High Temperature Metallic Alloys Advanced manufacturing (AM) technologies can play an important role in reducing the fabrication costs of fission reactor components. Powder Metallurgy-Hot Isostatic Pressing (PM-HIP) shares many of the cost-saving attributes of the other AM methods such as powder bed fusion and directed energy deposition. Also, PM-HIP is a competitive and proven AM technology that is used in many non-nuclear industries to fabricate structural components. It can be readily deployed for advanced reactor applications. However, recent tests conducted on PM-HIP structural materials showed that while the mechanical properties are comparable to or better than wrought product at low temperatures, the high-temperature cyclic performance is less favorable. This is a challenge for advanced reactor applications, as creep-fatigue damage due to thermal transients from reactor operations is the most severe structural failure mode. The cause of the degradation in cyclic properties is currently not known, but it could be due to powder compositions, oxygen content, processing conditions, etc. Applications are sought to develop an improved PM-HIP process for high-temperature alloys, including powder chemistry specification, powder manufacturing, container manufacturing, container filling and outgassing, hipping parameters, container removal, etc., so that the high-temperature fatigue, creep, and creep-fatigue properties of the fabricated components are the same as or exceed those of wrought product for very long design lifetimes. Questions Contact: Sue Lesica, sue.lesica@nuclear.energy.gov c. Simultaneous Measurement of Density and Viscosity for High-Temperature Molten Salts High-temperature molten chlorides and molten fluorides are used as a liquid fuel medium and as a heat transfer fluid in several advanced reactor systems as well as heat storage and heat transfer fluids for concentrated solar power. These low-viscosity molten salts typically have a viscosity < 10 cP (< 0.01 Pa s) depending on temperature and composition. Both the design and operation of these systems require viscosity and density measurements of the chosen salt system as a function of composition and temperature. Presently, a database of thermophysical properties of molten salts is being compiled from literature data as well as from new experimental measurements to support the design of molten salt-based systems. The concerted effort to make new measurements would benefit from new accurate high-throughput devices capable of measuring viscosity and density of high-temperature molten salts as a function of temperature. Operation of these molten salt systems typically involves pumping molten salts through heat exchangers and therefore would benefit from a real-time in-line or at-line device for measurement of density and viscosity of molten chloride and molten fluoride salts. These laboratory and monitoring devices must be capable of making high-precision measurements of viscosity and density at temperatures up to 800 C. For reactor applications the devices must not be affected by ionizing radiation. Possible viscosity and density measurement techniques that could be adapted to high-temperature measurements of viscosity and density include vibrating cantilevers7 and microfluidic-based methods.8 Questions Contact: James Willit, James.Willit@nuclear.energy.gov d. Other In addition to the specific subtopics listed above, the Department invites grant applications in other areas that fall within the scope of the topic description above.
