Influence of the microstructure on hydrogen diffusion in FeZr alloys

Abstract

The influence of the microstructure on the relaxation behaviour of hydrogen in partially crystallized nano- and microcrystalline Fe₉₀Zr₁₀ as well as in single-phase Fe₂Zr was investigated in the temperature range between 4.2 and 500 K by means of magnetic after-effect measurements. Reorientation processes of hydrogen in amorphous, grain boundary and crystalline phases led to characteristic relaxation maxima and activation enthalpies which were assigned to hydrogen jumps between anisotropic interstitial sites within the different structures. In addition, the degassing kinetics above 300 K were studied and allow a more detailed correlation between relaxation processes and microstructures.