Microstructure simulation of AA2219 alloy in hot/warm forming and heat treatment using cellular automata methods

The preparation of component with 2219 aluminum alloy consists of hot/warm forming and the subsequent heat treatment, inducing complex microstructure evolution. The microstructure simulation in forming and solution treatments is investigated using cellular automata (CA) models, consisting of initial microstructure generation model, static recrystallization (SRX) model and thermal-mechanical treatment model. The effect of parameters (temperature, strain, strain rate and pass interval time) on the microstructure characteristic is analyzed. SRX occurs during the pass interval time by the transformation from low-angle grain boundaries into high-angle grain boundaries. Low temperature, large strain and strain rate during the hot compression contribute to the SRX process during pass interval time due to the resulted higher dislocation. Warm forming is beneficial for the increased dislocation density and sub-grain structures, which change to equiaxed grains after solution treatment, indicating the total recrystallization. The increased strain and strain rate, and lower temperature in the warm forming process contribute to the grain refinement and acceleration of the velocity of the SRX process after solution treatment. Experiments of hot compression, warm compression followed by solution treatment are conducted. The CA simulated flow stress and microstructure agree with the experimental results. The CA models established can provide guidance for the microstructure evolution for the hot/warm forming and the subsequent heat treatment of aluminum alloy.

Automated summary

The preparation of 2219 aluminum alloy component involves hot/warm forming and subsequent heat treatment, resulting in complex microstructure evolution. Cellular automata (CA) models are used to simulate microstructure during forming and solution treatments. The effect of parameters on the microstructure characteristic is analyzed. The CA models provide guidance for microstructure evolution in aluminum alloy processing.