Dresden 2011 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
MM: Fachverband Metall- und Materialphysik
MM 12: Postersitzung I
MM 12.20: Poster
Monday, March 14, 2011, 17:30–19:00, P5
Phonon Contribution to the Thermodynamics of Pure and Mixed Clusters in bcc-Fe — •Mina Talati1, Matthias Posselt1, Giovanni Bonny2, Ahmed Tamer Al-Motasem1, and Frank Bergner1 — 1Helmholtz-Zentrum Dresden-Rossendorf (HZDR), P.O.Box 510119, D-01314 Dresden, Germany — 2Nuclear Materials Science Institute, SCK-CEN, Boeretang 200, B-2400 Mol, Belgium
The irradiation-enhanced nanostructural evolution in reactor pressure vessel steels is a multiscale phenomenon. It can be effectively studied by rate theory for which necessary parameters must be obtained through atomistic simulations. The present work focuses on the phonon contribution to the thermodynamics of nanoclusters consisting of vacancy and/or Cu. In all calculations the most recent Fe-Cu interatomic potential developed by Pasianot and Malerba is employed. The vibrational density of states determined by the dynamical matrix method is used to calculate the phonon contribution to free energy of formation and free binding energy of the clusters. Pure bcc-Fe and pure fcc-Cu are used as references in the calculation of the free energy of formation. The vibrational contribution to the total free energy of these metals determined in this work is compared with available CALPHAD data and with literature data obtained by first-principle methods or interatomic potentials. In the case of pure vacancy clusters and for many mixed vacancy-Cu clusters the absolute value of the total free binding energy decreases with increasing temperature. Pure Cu clusters show the opposite behavior.