Optimization of Hot Workability and Microstructural Control in Direct Chill Cast and Homogenized Aluminum-Copper Alloy AA2219
摘要
The study of hot deformation behavior of as-cast AA2219 aluminum alloy is essential for optimizing thermomechanical processing and controlling microstructural evolution, ensuring high-performance aerospace components. Uniaxial hot compression tests were conducted on direct chill cast and homogenized AA2219 alloy to study the flow behavior and consecutive microstructure evolution, in the deformation temperature range of 325–500 °C and strain rate of 0.001–10 s−1. The flow stress deviation caused by the frictional effect and the adiabatic temperature rise was corrected. The peak stress reduced with increasing temperature and decreasing strain rate. Based on the experimental results, the constitutive equation representing hot deformation behavior was developed using the Arrhenius-type model. The activation energy was estimated to be 159.6 kJ/mol, indicating the prime softening mechanism as dynamic recovery. Optimum hot working conditions (375–425 °C/0.001 s−1) are suggested based on contour maps of strain rate sensitivity parameter and efficiency of power dissipation.