Irreversible structural relaxation in a bulk Pd-Cu-Ni-P metallic glass

The evolution of the shear modulus and the damping decrement during irreversible structural relaxation in a bulk Pd₄₀Cu₃₀Ni₁₀P₂₀ metallic glass in a temperature range below the glass transition temperature has been studied with an inverse torsion pendulum at a frequency of ～25 Hz. It is shown that the irreversible relaxation can be recovered via quenching from temperatures above the glass transition temperature. The spectrum shape, the characteristic activation energies, and the attempt frequencies of the irreversible structural relaxation are estimated.