Optimization of thermal deformation process parameters of 2219 Al matrix composites

To investigate the deformation behavior and optimize the hot processing parameters for 2219 aluminum matrix composite, the constitutive equation and hot processing maps were established. Initially, hot compression experiments on 2219 aluminum alloy (2219A) were conducted using a Gleeble-3500 thermal simulation tester to obtain high-temperature rheological data. The deformation temperatures tested were 573, 623, 673, 723, and 773 K, with strain rates of 0.01, 0.1, 1, and 10 s^-1, and a maximum deformation of 60 %. Subsequently, material parameters such as the activation energy, Zener-Hollomon parameter, power dissipation efficiency, and instability coefficient for 2219A were calculated. Analytical expressions for these material and deformation parameters were formulated, and a hot processing map for 2219A was constructed. The hot processing map, along with the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) and the Entropy Weight Method (EWM), were used to optimize the thermal deformation process parameters. The stability processing area and the optimal processing area identified by both methods were largely consistent. According to the hot processing map, the stability processing areas were identified in the temperature ranges of 580-660 K and 690-773 K with strain rates of 0.01 s^-1 and 0.01-0.6 s^-1, respectively. Using the TOPSIS and EWM methods, the stability processing areas were defined between 573 and 640 K and 0.01 s^-1, 640-690 K and 0.01-0.1 s^-1, and 690-773 K and 0.01-1 s^-1. The consistency and accuracy of these optimization results were confirmed through microstructure analysis.