Anisotropic Mechanical Behavior and Microstructural Characteristics of AA2099-T83 Alloy Sheet: Experiment and Simulation

Mechanical anisotropy remains a highly regarded topic in the application of Al-Li alloy sheet. The microcosmic factors affecting mechanical anisotropy and the deformation characteristics within and between grains of this alloy during tensile deformation still require further elucidation. In this study, uniaxial tensile experiments were conducted on AA2099-T83 Al-Li alloy sheet along different directions, and the mechanical response, as well as the variations in stress and strain within and between grains, was predicted using the crystal plasticity finite element method (CPFEM). The results show that AA2099-T83 sheet display significant anisotropy in yield strength and elongation. The uneven distribution of the T₁ phase predominantly influences strength anisotropy, whereas texture and grain morphology have a lesser impact. CPFEM simulations at a true strain of 0.06 reveal that texture significantly affects elongation anisotropy, with the strain distribution of grains with a preferred orientation in 0° and 90° tensile directions aligning with the model’s overall strain distribution pattern. Notably, samples stretched at 90° demonstrate a higher strain gradient between grains, potentially increasing the likelihood of crack initiation.