A milling deformation model for aluminum alloy frame-shaped workpieces caused by residual stress
Keywords:frame-shaped workpieces, finite element simulation, residual stress, milling deformation model
In order to study the machining distortion of aluminum alloy 7050 caused by residual stress,based on the elastic theory, the machining deformation prediction model of plate was built .The deformation of aluminum alloy plate with two-way 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 using MSC.Marc software. The influences of initial residual stress, 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, and equations of the correction coefficients were deduced by nonlinear regression. 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 biggest error is 11.76%. This model is useful for the calculation of the machining deformation of aluminum alloy frame-shaped workpieces.