Internal friction of hydrogen-doped metallic glasses

The hydrogen internal friction (HIF) has been measured for six multi-component metallic glasses. The HIF peak is quite broad with the peak temperature Tp decreasing with increasing peak height, Qp−1. Qp−1 versus Tp relation is quite different among the alloys, suggesting a variety of hydrogen site energy distribution depending on the alloy composition. Considering the fact that two-level systems in metallic glasses for hydrogen jump are far from ideal, the observed relaxation strength is impossible to be interpreted in terms of a Snoek-type relaxation mechanism. A new hydrogen relaxation mechanism of a microscopic Gorsky effect has been proposed, where a large heterogeneity of elastic modulus in amorphous structure causes stress-induced hydrogen redistribution in a microscopic scale.