Regensburg 2019 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

MM: Fachverband Metall- und Materialphysik

MM 27: Methods in Computational Materials Modelling (methodological aspects, numerics)

MM 27.4: Vortrag

Mittwoch, 3. April 2019, 15:45–16:00, H44

Multi-Scale Modelling of Guinier-Preston Zone Formation in Al-Cu Alloys — •Tobias Stegmüller and Ferdinand Haider — University of Augsburg, Institute for Physics, Chair for Experimental Physics I, 86135 Augsburg, Germany

The investigation of precipitation processes in modern aluminium alloys plays an important role for the design of many material properties like strength or corrosion resistance. The influence of ageing time and temperature constitute the key for a quantitative understanding of precipitate formation.

The prediction of the evolution of the precipitate size distribution is a powerful tool for the characterisation of an alloy temper state. In this work a multi-scale approach, covering nucleation, growth and coarsening of early stage precipitates in binary Al-Cu alloys, the Guinier-Preston zones (GPZ), will be presented. Starting from DFT calculations and Cluster Expansion construction, followed by Monte Carlo free energy calculations, a meso-scale Cluster Dynamics model is constructed. By following this approach, the model is able to predict the evolution of size distributions of GPZ for different alloy compositions and ageing temperatures.

To validate the model, kinetic Monte Carlo simulations on the precipitation of GPZ were performed and the results for the evolution of average precipitate size, precipitated fraction of solute and the number density of precipitates agree well with the results obtained by Cluster Dynamics. The formulation of the multi-scale approach, its results and the comparison to the Monte Carlo simulations will be presented.