Hot Deformation Behavior and Constitutive Modeling of 2219 Aluminum Alloy for Ring Rolling Applications

2219 aluminum alloy is widely used in aerospace components because of its high specific strength, excellent fracture toughness, and resistance to stress corrosion cracking. Accurate characterization of its hot deformation behavior is important for the numerical simulation and process design of ring rolling. In this study, isothermal compression tests were carried out on a thermal–mechanical simulator at temperatures of 380–460 °C and strain rates of 0.01–10 s⁻¹ to investigate the hot deformation behavior of 2219 aluminum alloy. The effects of deformation temperature and strain rate on flow stress evolution were analyzed based on the experimental results. A strain-compensated Arrhenius-type constitutive model was developed to describe the flow stress behavior over a wide strain range. The material constants, including the stress exponent, stress level parameter, activation energy for hot deformation, and structure factor, were determined by regression analysis, and their strain dependence was expressed as polynomial functions of true strain. The model was evaluated by comparing predicted and experimental flow stress values, giving an average absolute error of 4.78%. The results indicate that the developed model can describe the combined effects of temperature, strain rate, and strain with good accuracy, and can be used for numerical simulation and process optimization in hot ring rolling.