Large-scale, high-strength aluminum alloy forgings are essential components in the aerospace industry, with benefits including increasing strength and decreasing weight. Accurate shape-property control is the secret to forging quality. This study uses the alloy 7050 to experimentally evaluate the parametric influence of cold compression on residual stress and mechanical characteristics. The evolutions of mechanical properties, microstructure and residual stress are theoretically studied using various cold compression strains from 1% to 5% on an equivalent part, of which the results are further applied on a complicated rib-structured die forging. It is demonstrated that increasing the compression strain reduces the tensile strength of the material, but has little impact on conductivity and fracture toughness. According to the TEM results, compression also encourages the precipitation and growth of precipitated phases, particularly in positions with high dislocation densities after aging. Cold compression significantly reduces residual stress; nevertheless, as compression strain increases, residual stress first decreases and then increases. With the use of rib-structured forging, it is observed that the compression strain for 7050 aluminum alloy ranges from 2% to 4%, and the combined pressing method of the rib and web improves the uniformity of residual stress.

The effects of 1%~5% cold compression on the mechanical properties, microstructure and residual stress of 7050 aluminum alloy were investigated, and the results were applied to the complex die forging with stiffener structure. The results show that with the increase of cold compression, the tensile strength of forging decreases gradually, but the conductivity and fracture toughness of the forging have little change. TEM microstructure shows that with larger cold compression (5%), the dislocation density was relatively higher, which promoted the precipitation and growth of precipitated phases at positions with higher dislocation density during aging process. The ultrasonic tests of residual stress show that with the increase of cold compression, the residual stress in the forging decreases first, and then increases when cold compression reaches 5%. The results of the die forging of 7050 aluminum alloy with bar structure show that the residual stress of the die forging is obviously eliminated after 2-4% cold compression, and the deformation after machining is obviously less than of the uncompressed forgings. The combination of bar and web is more beneficial to the uniform distribution of residual stress of the die forging with bar structure.