Assessment of effective elastic constants of U-10Mo fuel: A multiscale modeling and homogenization study

• Published in: Journal of nuclear materials Vol. 599; p. 155225
• Main Authors: Kadambi, Sourabh B., Aagesen, Larry K., Zhang, Yongfeng, Beeler, Benjamin
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.10.2024
• Subjects: Asymptotic expansion homogenization; Effective elastic constants; Fission gas bubbles; Intergranular porosity; Monolithic U-10Mo; Phase-field model; Ronchi equation of state; Asymptotic expansion homogenization; Fission gas bubbles; Phase-field model; Monolithic U-10Mo; Ronchi equation of state; Intergranular porosity; Effective elastic constants
• ISSN: 0022-3115; 1873-4820
• DOI: 10.1016/j.jnucmat.2024.155225

The significant microstructural changes that U-Mo fuel undergoes during operation degrades its mechanical properties and structural integrity. Microstructural evolution entails the formation, evolution, and redistribution of porosity in conjunction with grain refinement. In the present paper, we employ numerical approaches to assess the impact of the various microstructural features—grains, nanoscale intragranular fission gas bubbles, and mesoscale intergranular voids—on the degradation of elastic constants. Phase-field microstructure models are combined with the asymptotic expansion homogenization technique in order to derive the effective elastic constants as a function of porosity and fission density. The results are verified and compared against theoretical bounds. Using this approach, elastic degradation in operating nuclear fuels can be quantified when the distributions of microstructural features are known.