Structural and hyperfine properties of Ti₄₈Zr₇Fe ₁₈ nano-compounds and its hydrides

It is well established that Ti-based nano-alloys are able to absorb hydrogen with relatively high hydrogen to metal ratio of 4/3. In this study the Ti₄₈Zr₇Fe₁₈ nano-compound, prepared by mechanical alloying (MA), has been investigated. In its initial state the compound is amorphous, however upon thermal treatment it transforms to the quasicrystalline icosahedral structure (i-phase), which is based on the Mackay cluster type. Structural characterization of the sample was made by means of XRD measurements. Thermodynamic properties were studied by differential scanning calorimetry (DSC) and thermal desorption spectroscopy (TDS). To find the influence of hydrogen and structure type on hyperfine interactions the Mössbauer spectroscopy (MS) experiment was performed, as well. The amorphous sample after MA was hydrogenated in order to unveil hydrogen influence on crystal properties of the sample. Upon hydrogenation of the amorphous sample a decomposition into simple hydrides took place.