Creation and annihilation of free volume during homogeneous flow of a metallic glass

Abstract

Bulk samples of Pd 41Ni 10Cu 29P 20 glass were tested at constant true stress (20-636 MPa) in compression at 550, 555, and 565 K to study the transition from steady-state creep at low stress to deformation-induced softening at high stress. In the high-stress regime strongly accelerating creep was observed. All deformation was homogeneous. The activation volume was 106 Å 3. The isoconfigurational activation energy was 9.03±0.64 eV. The disordering rate is proportional to the applied power density (stress × strain rate). The disordering process is inefficient in energy and in the production of free volume. © 2005 American Institute of Physics.