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During the operation of material removal, the release and re-distribution of residual stresses is crucial to machining deformations of aircraft structural parts. Hence, the non-uniform plastic deformations, which caused by the high temperature gradient field in the quenching process, will give rise to residual stresses. Therefore, the finite element model is established for the quenching process according to the convective heat transfer coefficient. Whether the amplitude or distribution, the simulated residual stresses are in good agreement with the experimental data. On this basis, the proposed method is further used to analyze the formation mechanism of residual stress in the quenching of 7075 aluminum alloy thick plate. It is concluded that the final residual stresses are already determined when the plastic deformations in the central layer is over at the end slip time. The residual stresses remain unchanged even if the temperature will continue to drop. Finally, the performance-controlled and deformation-controlled method is suggested for residual stresses. It is known that the deformation-controlled region can strongly impact the final residual stresses whereas the performance-controlled region has a few changes of the final residual stresses. Consequently, the decrease of the convective heat transfer coefficient in the deformation-controlled region and the increase in the performance-controlled region, can fast the cooling velocity and reduce the final residual stress.