The Application of CALPHAD Calculations to Uranium-Based Metallic Nuclear Fuels

A Phase-Field Study of Spinodal Decomposition Impeded by Irradiation in U-Mo and U-Mo-Zr Alloys

“…E G γ is the excess free energy corresponding to the heat of mixing. The thermodynamic parameters of the U-Mo and U-Mo-Zr system utilized in this work are imported from with the CALPHAD database [12,46].…”

“…The thermodynamic parameters describing the Gibbs free energy of the Bcc phase in the U-Mo-Zr system are listed in Table 2. Utilizing the thermodynamic database [12], the isothermal sections of the U-Mo-Zr ternary system were calculated at temperatures of 673 K, 773 K and 873 K, as depicted in Figure 5, where the red dots in the figures are the initial alloy compositions used for the following phase-field simulations. It can be seen that the U-Mo-Zr alloy has wide two-phase and three-phase miscibility gaps within the 673-873 K range.…”

“…Table 2. The thermodynamic parameters of the U-Mo-Zr system [12]. When the aging time is 4500 s, the evolutions of the concentration profile of the U-10 at.% Mo-20 at.% Zr alloy at different temperatures are shown in Figure 7a.…”

“…Recently, research on U-Zr alloys has indicated that the spinodal decomposition of the γ-phase can effectively inhibit irradiation swelling [7,8]. The γ-phase generally appears in uranium-based alloys, such as U-Mo, U-Nb, U-Zr and U-Mo-Zr alloys [9][10][11][12]. Therefore, the study of spinodaldecomposed microstructures with stable γ-phases in uranium-based metallic nuclear fuels has important guiding significance for the development of nuclear fuels.…”

Effect of irradiation-induced cascade mixing on spinodal decomposition in U–Nb and U–Zr alloys: a phase field study

“…The thermodynamic data in eqn (3) are obtained from the U-Nb and U-Zr thermodynamic assessment. 7,40 The governing equations describing the spatial and temporal evolutions of composition is determined by the Cahn-Hilliard-type equation with a forced mixing term:…”