Dresden 2006 – wissenschaftliches Programm

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MM: Metall- und Materialphysik

MM 8: Symposium Modern Metallic Materials Design II

MM 8.4: Vortrag

Montag, 27. März 2006, 15:30–15:45, IFW B

Monte-Carlo-Simulation of Nucleation of GP-Zones in Al-Cu-Alloys — •Andreas Lammerschop, Volker Mohles, and Günter Gottstein — Institute of Physical Metallurgy and Metal Physics, RWTH Aachen, Kopernikusstr. 14, 52056 Aachen

Age-hardening by precipitation is one of the most important mechanisms for strengthening of Al-alloys. We present an atomistic Monte-Carlo-Model for calculations on an f.c.c.-lattice. Diffusion is implemented by a vacancy mechanism. The thermodynamic driving force is represented as a regular solution model based on the bonding energies of the nearest and next nearest neighbours. The elastic energy model is based on the concept proposed by Eshelby and Khachaturyan. As to be expected from experiments, the simulations show that precipitations nucleate parallel to {100}-planes. This is actually caused by the elastic energy. In these MC-simulations, the thermodynamic energetics used have been based on experiments. The coupling of this model with quantum theory calculations (DFT) will improve the understanding of the formation process. Moreover it will enable true predictions on the precipitation kinetics in other f.c.c.-alloys.