Study on the quality stability of rolling distortion correction in aluminum alloy aerospace structural components

Abstract

The aim of the present study was to evaluate the quality stability of roll-corrected 7050-T451 aluminum alloy structural components under operational loading conditions, in order to provide a new method for accurate prediction and control of machining deformation of aluminum alloy structural components. Mechanical load and double-sided rolling test device were designed and constructed based on the mechanical structure and control unit. Subsequently, the quality stability of the specimen was investigated by characterizing the correction dimensions, residual stress, and fatigue fracture morphology under different rolling correction and mechanical force load. The results demonstrate that the ultimate load (F) is 3200 N as the sample undergoes plastic deformation. Compared to post-rolling correction, the deformation of the specimens after 1000 loading cycles at 60% F, 70% F, 80% F and 90% F represented only 11.45%, 9.85%, 9.03% and 4.12% of their dimensions following rolling correction, accompanied by average residual stress variations of 2.37%, 9.19%, 3.43% and 0.92%, respectively. Further, as the number of loading cycles increased, the deformation after 10, 100, 1000 and 10000 cycles at 80% F constituted only 9.03%, 7.40%, 9.76% and 7.23% of the post-rolling correction dimensions, with corresponding average residual stress variations of 3.43%, 3.96%, 2.44% and 4.78%. No significant changes were observed in the macroscopic dimensions or residual stress of the specimens. After rolling, the fatigue crack initiation site shifted from the surface to the subsurface, and the average fatigue striation spacing in the crack propagation zone decreased, indicating an improvement in fatigue performance. This demonstrates that aluminum alloy aerospace structural components exhibit high-quality stability in all aspects after rolling correction.