Compatibilities and interfacial diffusions between U–10Zr alloy and Zircaloy-4 alloy

Abstract U–10Zr/Zircaloy-4 (U–10Zr/Zr-4) diffusion couples were prepared by a coating and hot-rolling method and the compatibilities of the U–10Zr/Zr-4 diffusion couples were investigated by metallographic microscope (OM), scanning electron microscope (SEM) and energy-dispersive spectroscopy (EDS) analysis. The results show that the interface layer of the U–10Zr/Zr-4 couple grows uniformly, no cracks and pores at the interface observed. The compositions of the interface layer of the U–10Zr/Zr-4 couple vary parabolically. From U–10Zr side to Zr-4 side, the content of U gradually decreases, while the content of Zr increases. Moreover, the growth of the interface layer of the U–10Zr/Zr-4 couple follows the parabolic growth law. The diffusion coefficient constant is 2.70E-1 m 2 /s and the diffusion activation energy is 260.49 × 10 3  J/mol. The diffusion coefficients at 750 °C and 800 °C are 1.33E-14 m 2 /s and 5.54E-14 m 2 /s respectively.