Impact of severe plastic deformation on the relaxation of glassy and supercooled liquid states of amorphous Pd$_{40}$Ni$_{40}$P$_{20}$

TL;DR

This study explores how severe plastic deformation affects the relaxation and structural order of amorphous Pd40Ni40P20, revealing a link between deformation, annealing, and medium-range order changes using calorimetry and electron microscopy.

Contribution

It introduces a novel analysis of the relationship between deformation-induced rejuvenation and relaxation in relation to medium-range order in metallic glasses.

Findings

Deformation influences calorimetric signals and medium-range order.

Coupling observed between exothermic peaks and MRO changes.

Potential energy landscape model explains MRO engineering in glasses.

Abstract

The impact of severe plastic deformation by high-pressure torsion on the relaxation of the glassy and supercooled liquid states of Pd$_{40}$Ni$_{40}$P$_{20}$ was investigated using a combination of differential scanning calorimetry, low-temperature heat capacity and fluctuation electron microscopy. The changes in the calorimetric signals due to deformation and subsequent heat treatments were analyzed and a correlation between deformation (rejuvenation) and annealing (relaxation) was found in relation to medium-range order (MRO). Moreover, a coupling between the occurrence of an exothermic peak in the supercooled liquid state and specific changes in the MRO types were identified. These findings are comprehended in a potential energy landscape scheme offering a new approach for MRO engineering of glasses.