Funding period: Aug 2018 to Jun 2022

Researcher: Rostyslav Nizinkovskyi

Wrap-up

Keywords: Phase-field method; Fe-Cu alloys; precipitate morphology; elastic interaction; stress effects

Background:
The influence of crystallographic strains in fcc/bcc precipitation systems on kinetics and nanostructural formation is not well researched.

Objective:
>> develop a theoretical framework and correspondent model to investigate the influence of crystallographic strains on precipitation phase transformation in fcc/bcc systems on example of Fe-Cu system

Methods:
Local and non-local phase-field models, finite-element method

Results:
A numerical efficient non-local phase-field model was developed to study equilibrium states of the elastically stressed precipitate phases. The influence of the eigenstrains on the precipitate phase morphology was verified. The stability of morphology to the applied stress was justified in coherence with the crystallographic strain framework. The eigenstrains have been shown to enhance the coarsening rates of the fcc-Cu precipitates.

Conclusions:
The developed phase-field model shows good agreement with experimental data and gives a coherent representation of precipitation reaction in fcc/bcc systems based on the example of the Fe-Cu system.

Originality:
The results of this work provide a theoretical framework for the understanding of precipitation reaction in coherence with previous crystallographic models, in such a way expanding their methodology on the new kind of predictions.