Effect ofSolution–ECAP–AgingTreatment on Microstructure and Properties of 7075 Aluminum Alloy

7075 aluminum alloy is widely used as a high-strength structural material in aerospace and other fields. However, its traditional casting and rolling process suffers from coarse grains and uneven distribution of secondary phases, which limits its performance potential. Therefore, this study proposes a multi-process coupling method that combines solution treatment, equal-channel angular pressing, and aging treatment. Solution treatment fully dissolves the strengthening phases into the matrix. Equal-channel angular pressing applies segmented temperature-controlled extrusion. Aging treatment promotes the precipitation of nanoscale phases. The L16 (45) orthogonal experiment validates the influence of each process on the alloy's microstructure and properties and also optimizes these influences. In performance tests, this method refines grains to the nanoscale (average 28 nm), increases hardness from 85 HV to 112 HV, enhances tensile strength to 562 MPa, improves elongation at fracture by 21.5 %, and raises electrical conductivity to 55 % IACS. These results indicate that the proposed multi-process coupling method effectively improves the microstructure and properties of 7075 aluminum alloy through synergy between low-temperature strengthening and medium-high-temperature plasticity optimization. This study offers technical and practical references for optimizing high-strength aluminum alloys.