Thermal-pressure treatment for tuning the atomic structure of metallic glass Cu-Zr

Abstract

Both thermal and pressure treatments are effective to obtain rejuvenated metallic glass (MG) with high energy state and densely packed structure. In this study, we studied the changes of potential energy and atomic volume under various cooling rate and pressure during quenching stage for Cu-Zr MGs by atomic structure analysis. It is found that: (1) Increasing pressure leads to monotonous increasing potential energy but decreasing and then increasing atomic volume; (2) The potential energy becomes higher, and the densest atomic structure is obtained at a higher pressure with more Cu content; (3) Higher energy state obtained by increasing pressure is corresponding to more full icosahedron and 1551 bond type. This work provides a profound understanding of rejuvenated MG with high energy and unique atomic structure by thermal-pressure treatments.