Rejuvenation by compressive elasto-static loading: The role of static stress on a Zr-based metallic glass

Calorimetric, mechanical, and microstructural characterizations are used to investigate the rejuvenation of Zr 55 Cu 30 Al 10 Ni 5 (at. %) bulk metallic glass (BMG) by elasto-static loading (ESL). The as-cast BMG samples are compressed at room temperature for 24 hours while being subjected to static stresses that ranged from 40%, 70%, 80%, and 90% of the yield stress. The BMG undergoes structural rejuvenation as a result of the compressive ESL treatment, increasing the free volume content at all applied static stresses. The amount of energy that has been stored, as determined by the relaxation exotherms that precede glass transition, appears to be a function of static stress and reaches a maximum of 13.2 J g −1 at the highest applied stress, which is twice the stored energy of the as-cast sample. A steady increase in plastic strain, a decline in hardness, and a fall in Young's modulus are linked to enthalpy rejuvenation of the BMG. According to microstructural investigations, ESL introduces structural heterogeneities into the BMG that are linked to structural dilatation at the short- and medium-range atomic scales. This study emphasizes rejuvenation as the main effect of ESL treatment on the BMG under study. • The rejuvenation behavior of Zr 55 Cu 30 Al 10 Ni 5 (at.%) BMG during compressive elasto-static loading treatment was studied. • As static stress increases, the exothermic relaxation enthalpy gets larger. • The larger amount of stored energy is associated with greater plasticity, lower hardness, and lower modulus in treated samples. • Elasto-static rejuvenation induces structural heterogeneities and atomic rearrangements.