Experimental techniques for investigating thermal transport in nuclear materials

ABSTRACT

The unique combination of large energy density and extreme environment inside a nuclear reactor imposes strict requirements on the thermal transport property of nuclear materials, which is significantly deteriorated by the irradiation damage, leading to increased service temperature, complex microstructural changes, and compromised integrity. To address this issue, tremendous efforts have been made over the years to measure, comprehend, and enhance thermal transport regulated by radiation-induced defects in advanced nuclear materials. Such efforts would be laborious and time-consuming without revolutionary innovations in characterization techniques. Herein, we review recent experimental studies on the thermal transport properties of nuclear materials, with a focus on the advancements in the measurement techniques with improved spatial resolutions. We provide a brief introduction to the mechanisms of thermal transport in nuclear materials and the impact of irradiation damage on thermal transport. A comprehensive review is presented of advanced thermal characterization techniques that encompass different length scales, ranging from millimeter to nanometer, along with their respective experimental outcomes. Finally, the practicality of each measurement technique is assessed, and research opportunities are discussed in regard to the development of physics-based fuel models.

KEYWORDS:

• Thermal transport
• irradiation effects
• characterization techniques
• subsized samples

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

Y.W. would like to acknowledge the support from National Natural Science Foundation of China (12305326) and the Fundamental Research Funds for the Central Universities, Sun Yat-sen University (23qnpy76). X.M. was supported by National Natural Science Foundation of China (U2032143, 12205392), Guangdong Major Project of Basic and Applied Basic Research (2019B030302011), Guangdong Provincial Major Youth Talents Project (2021TQ06L123), Guangdong Provincial International Sci & Tech Cooperation Program (2020A0505020005), and Zhuhai-Hong Kong-Macao Science and Technology Cooperation Project (ZH2207-7301-210009-P-WC). Z.C. was supported by National Natural Science Foundation of China (21978279). M.K. acknowledges support by the Center for Thermal Energy Transport under Irradiation (TETI), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, and Office of Basic Energy Sciences.