Electrochemical Formation of Hydride Phases on the Zirconium- 1% Niobium Alloy Used in Nuclear Fuel Cladding

Abstract

Investigation into the destructive effects of the hydride formation on the zirconium fuel claddings, involves working with radioactive materials. In order to avoid this problem, in this study, zirconium hydride phases were created on the Zr-1%Nb alloy (used in nuclear fuel cladding), by the electrochemical charging method. The experiments were carried out in 0.017 M NaCl aqueous solution at room temperature. The samples were analyzed by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the protective oxide layer had been destroyed, and Zr-H-Zr and Zr-H bonds were formed on the surface. In addition, by diffusion and increasing the hydrogen concentration in the bulk, ZrH2 and ZrH hydride phases had been formed in addition to the cracks in the sample, because these phases had about 10% difference in volume with the zirconium phase.

Keywords

• fuel claddings
• hydrogen embrittlement
• zirconium hydride
• electrochemical hydrogenation