Host and hydrogen diffusion in an NiZr metallic glass

Abstract

Anelastic relaxation measurements have been used to study atomic mobility in glassy Ni 40Zr 60, before and after the introuction of hydrogen to the level [ H]/[ M] = 0.78. By the combined use of the long-range Gorsky relaxation and the short-range reorientation relaxation, the motion of hydrogen has been observed over an extended temperature range and found to deviate from Arrhenius behavior below 140 K. The distribution of reorientation relaxation times is approximately log-normal, with a single maximum whose width increases to 5 decades at 100 K. The introduction of hydrogen has been found to accelerate relaxation behavior associated with the motion of host atoms. This represents a new effect, termed hydrogen-enhanced host diffusion.