Low-frequency high-temperature internal friction of bulk metallic glasses

The internal friction (IF) of Johnson alloy (Zr-Ti-Cu-Ni-Be) glass prepared by a single-roller melt-spinning method was measured using an inverted torsion pendulum with the free decay method. The measurements were performed from room temperature, through the glass transition temperature T-g, up to the crystallization temperature T-x. The effect of isothermal annealing at a temperature about 20 K below T-g was studied. By the annealing the unstable glassy state and the metastable supercooled state were transferred to more stable ones (stabilization). In a well-stabilized state, the background IF was flat at lower temperatures, increased rapidly at higher temperatures, and an IF peak appeared near T-x together with another peak at a lower temperature. No IF peak was observed near T-g. Qualitative discussions are presented for the experimental results, and possible use of the glass as a high damping material is briefly mentioned. (C) 2003 Elsevier Science B.V. All rights reserved.