|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Dynamic Behavior of Materials VIII
||Spall Failure Mediated by Vacancy Clustering and Subsequent Nano-void Growth
||Sara Adibi, Justin Wilkerson
|On-Site Speaker (Planned)
Ductile failure of metals is usually prompted by void nucleation, growth, and coalescence. Recent experimental observations suggest that under extreme loading conditions nanovoid nucleation can be associated with vacancy aggregation and clustering in contrast to the traditional view of void nucleation at second phase particles. Here, we use molecular dynamics (MD) simulations to investigate the time associated with vacancy clustering in high purity metals. It is shown that increasing the temperature and/or initial vacancy concentration can accelerate the clustering process. Furthermore, since the critical stress to grow a nanovoid is strongly size-dependent, an interesting time-temperature-vacancy concentration coupling is predicted by our simulations. We propose a continuum theory for this diffusion-fracture coupled process, which is shown to provide favorable agreement with our MD simulations. This atomistically-informed theory of void nucleation may be integrated into multiscale frameworks of ductile fracture of metals to predict the macroscopic implications of these atomistic processes.
||Planned: Supplemental Proceedings volume