Effect of thermomechanical treatment on the microstructure, phase composition, and mechanical properties of Al-Cu-Mn-Mg-Zr alloy

The effect of the thermomechanical treatment on the microstructure, phase composition, and mechanical properties of heat-treatable AA2519 aluminum alloy (according to the classification of the Aluminum Association) has been considered. After solid-solution treatment, quenching, and artificial aging (T6 treatment) at 180A degrees C for the peak strength, the yield stress, ultimate tensile strength, and elongation to failure are similar to 300 MPa, 435 MPa, and 21.7%, respectively. It has been shown that treatments that include intermediate plastic deformations with degrees of 7 and 15% (T87 and T815 treatments, respectively) have a significant effect on the phase composition and morphology of strengthening particles precipitated during peak aging T8X type, where X is pre-strain percent, treatments initiate the precipitation of significant amounts of particles of the theta'- and Omega-phases. After T6 treatment, predominantly homogeneously distributed particles of theta aEuro(3)-phase have been observed. Changes in the microstructure and phase composition of the AA2519 alloy, which are caused by intermediate deformation, lead to a significant increase in the yield stress and ultimate tensile strength (by similar to 40 and similar to 8%, respectively), whereas the plasticity decreases by 40-50%.