Abstract
Molecular dynamics simulations of cavitation in a Zr(50)Cu(50) metallic glass exhibit a waiting time dependent cavitation rate. On short time scales nucleation rates and critical cavity sizes are commensurate with a classical theory of nucleation that accounts for both the plastic dissipation during cavitation and the cavity size dependence of the surface energy. All but one parameter, the Tolman length, can be extracted directly from independent calculations or estimated from physical principles. On longer time scales strain aging in the form of shear relaxations results in a systematic decrease of cavitation rate. The high cavitation rates that arise due to the suppression of the surface energy in small cavities provide a possible explanation for the quasibrittle fracture observed in metallic glasses.
Highlights
Amorphous materials, commonly termed glasses when quenched from the melt, occur in every class of material including ceramics, metals, and polymers
Molecular dynamics simulations of cavitation in a Zr50Cu50 metallic glass exhibit a waiting time dependent cavitation rate
On short time scales nucleation rates and critical cavity sizes are commensurate with a classical theory of nucleation that accounts for both the plastic dissipation during cavitation and the cavity size dependence of the surface energy
Summary
Commonly termed glasses when quenched from the melt, occur in every class of material including ceramics, metals, and polymers. We compare our simulation results in Zr50Cu50 to the theoretical predictions and show that a classical nucleation theory (CNT) that includes the effects of plastic flow and curvature dependent surface energy is valid on short time scales, while on longer time scales strain aging effects become important.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.