A milling deformation model for aluminum alloy frame-shaped workpieces caused by residual stress

For the purpose to predict the machining distortion of aluminum alloy 7050 caused by residual stress, a milling deformation model of plate was built based on the elastic theory. The deformation of aluminum alloy plate with residual stress after whole layer milled was studied. On the basis of the amendment of the machining deformation prediction model of the plate, machining deformation model of aluminum alloy frame-shaped workpieces was established, which contains undetermined correction coefficients and evaluation parameter of milling deformation. In order to confirm the undetermined coefficients, several finite element models of the milling process of thick aluminum alloy plate were established by MSC. Marc software. The influences of the number of slots and milling rate on the milling deformation of thick aluminum alloy plate were analyzed. The FEM results show that correction coefficients mainly depend on milling rates when residual stress is constant. Equations of the correction coefficients were deduced by multivariate regressive analysis. Then the accuracy of this model was proved by experiment. The test results show that this model can accurately predict the machining deformation of aluminum alloy frame-shaped workpieces caused by residual stress and the largest error is 15.8%. This model provides guidanceto the calculation of the machining deformation of aluminum alloy frame-shaped workpieces.