Hydrogen Kinetics and Hydride Formation Effect on Zr-1Nb and Zr-1Nb-1Sn-0.1Fe Alloys for Nuclear Application

The purpose of this study was to investigate the kinetics of hydrogen absorption and hydride formation and their effect on the mechanical properties in Zr-1Nb and Zr-1Nb-1Sn-0.1Fe alloys, which were thermomechanically processed and gaseously hydrided at 320ºC under 10 bar hydrogen pressure. X-ray diffraction (XRD) confirmed the formation of α-Zr matrix after final heat treatment. The alloys absorbed almost the same amount of hydrogen, although with different kinetics. Absorption began almost immediately in Zr-1Nb alloy whilst in Zr-1Nb-1Sn-0.1Fe hydrogen absorption started after 11 h besides a faster hydrogen kinetics. Results showed that tensile strengths for both alloys were nearly independent of absorbed hydrogen. Fractographic examinations indicated ductile fractures for unhydrided condition whereas quasi-cleavage features were observed for all hydrided specimens.

本研究旨在探究Zr-1Nb与Zr-1Nb-1Sn-0.1Fe合金的吸氢动力学、氢化物形成行为，及其对合金力学性能的影响。上述合金均经过热机械加工，并于320℃、10巴氢气压力下进行气态氢化处理。X射线衍射（X-ray diffraction, XRD）证实，经最终热处理后合金基体为α-Zr相。两种合金的吸氢总量近乎一致，但动力学特征存在显著差异：Zr-1Nb合金几乎可即刻启动吸氢过程，而Zr-1Nb-1Sn-0.1Fe合金则在11小时后才开始吸氢，且其氢吸收动力学速率更快。研究结果表明，两种合金的抗拉强度几乎不受吸氢量的影响。断口形貌分析显示，未氢化试样呈现韧性断裂特征，而所有氢化试样均观察到准解理断裂形貌。