Modeling of whole process of ageing precipitation and strengthening in
Al-Cu-Mg-Ag alloys with high Cu-to-Mg mass ratio
Al-Cu-Mg-Ag alloys with high Cu-to-Mg mass ratio
(1. Key Laboratory of Nonferrous Metal Materials Science and Engineering, Ministry of Education,
Central South University, Changsha 410083, China;
2. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
3. Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,
Wuhan University of Science and Technology, Wuhan 430081, China)
Central South University, Changsha 410083, China;
2. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
3. Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,
Wuhan University of Science and Technology, Wuhan 430081, China)
Abstract: A physically based numerical model to predict the microstructure evolution and yield strength of high Cu-to-Mg mass ratio Al-Cu-Mg-Ag alloys during the whole ageing process was developed. A thermodynamically-based precipitation model, employing the classical nucleation and growth theories, was adapted to deal with the precipitation kinetics (evolution of radius and volume fraction of precipitates for Ω phase) of aged Al-Cu-Mg-Ag alloys. The model gives an estimation of the precipitation kinetics (evolution of radius and density of precipitates for both θ′ and Ω phases) of the alloy. The strengthening model based on Orowan mechanism was deduced. The microstructural development and strength predictions of the model are generally in good agreement with the experimental data.
Key words: ageing; precipitation; modeling; microstructure; thermodynamics; strengthening