Microstructure Evolution and Mechanical Properties of 7050 Aluminum Alloy During Two‐Stage Heat Treatment

Al–Zn–Mg–Cu alloys are indispensable high‐strength materials in aerospace and automotive industries, but limited room‐temperature formability hinders their wider application. To address this, this study systematically evaluates the effects of a two‐stage heat treatment on the microstructure evolution and mechanical properties of this alloy. Results show that secondary phase dissolution through grain boundary phase breakdown and intragranular phase fragmentation improves room‐temperature plasticity, whereas excessive thermal exposure triggers grain coarsening and overburning. An optimized regime (470 °C/60 min + 480 °C/80 min) reconciles this trade‐off, achieving efficient phase dissolution with an overburning area fraction of 0.03%. This process yields a high elongation of 15.19%, representing a 228.1% increase over the initial state, and reduces the yield ratio to 0.74. The enhanced plasticity is associated with extensive secondary phase dissolution, reduced potential crack‐initiation sites, weakened Zener pinning, and the development of Cube, Goss, E, F, and Rotated Cube textures. This crystallographic configuration maintains a high average Schmid factor of 0.45 and a low Taylor factor of 3.05, facilitating multi‐slip activity and homogeneous plastic deformation. These microstructural and crystallographic changes promote microvoid growth and coalescence and improve the room‐temperature plastic deformation capacity.