Significant structural relaxation in a Mo[sbnd]O binary amorphous alloy

We revealed the significant structural relaxation with unprecedent hardness increment of 120% in an electrodeposited amorphous Mo[sbnd]O alloy upon annealing, which is much higher than that in the conventional metallic glasses (<15%). The relaxation kinetics was well described by a stretched exponential function with a Kohlrausch index of 0.51 and relaxation time of 115 s at 623 K. In addition, the significant structural relaxation was also reflected by a much higher creep resistance and smaller strain rate sensitivity after annealing. The significant hardness increment suggested that the as-deposited amorphous alloy has a highly disordered glassy state equivalently obtained by quenching at ~10 ¹² K s ⁻¹ . This was consistent with the structural observation that the as-deposited amorphous alloy has a low volume fraction (7%) of icosahedral-like medium range ordered (IMRO) clusters. Upon annealing, significant structural relaxation stemmed from the structural ordering, where the volume fraction of IMRO clusters increased to 19%.