Structurally enhanced anelasticity in Zr-based bulk metallic glasses

Atomic force acoustic microscopy was used to image bulk metallic glasses of composition Zr63−xCu24AlxNi10Co3 with 8 < x < 15. The elastic contrast was modulated on a length scale of 250–400 nm. A similar modulation was identified by transmission electron microscopy. Using the thermoelastic, model a good correlation between the observed anelasticity and the evidenced mesostructure was obtained.

Research highlights
► The authors reports on the occurrence of mesostructure in the Zr63−xCu24AlxNi10Co3 with a length scale in the 250–400 nm range, depending on the aluminum content.
► The frequency dependence of the longitudinal sound velocity correlates with the measured mesostructural lengths while interpreting the ultrasonic data with the thermoelastic model.
► It appears that the mesostructural length scale is a governing parameter for the mechanical behavior of this alloys system.
► The present work first demonstrates the interplay of mesostructure and mechanical behavior of metallic glasses.