title: Mechanism of void nucleation and growth in bcc Fe: atomistic simulations at experimental time scales.
abstract: Evolution of small-vacancy clusters in bcc Fe is simulated using a multiscale approach coupling an atomistic activation-relaxation method for sampling transition-state pathways with environment-dependent reaction coordinate calculations and a kinetic Monte Carlo simulation to reach time scales on the order of ~10⁴ s. Under vacancy-supersaturated condition, di- and trivacancy clusters form and grow by coalescence (Ostwald ripening). For cluster size greater than four we find a transition temperature of 150 °C for accelerated cluster growth, as observed in positron annihilation spectroscopy experiments. Implications for the mechanism of stage-IV radiation-damage-recovery kinetics are discussed.
authors.affiliation: Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
authors.forename: Yue
authors.initials: Y
authors.lastname: Fan
authors.forename: Akihiro
authors.initials: A
authors.lastname: Kushima
authors.forename: Sidney
authors.initials: S
authors.lastname: Yip
authors.forename: Bilge
authors.initials: B
authors.lastname: Yildiz