Simulation of Process Induced Part Distortion for Milling of Aircraft Components

During the machining of structural components, material inherent stresses are removed and additional residual stresses are induced into the boundary layer of the workpiece. Both effects can result in distortions of the workpiece geometry which leads to geometrical errors and time consuming repair processes. The research objective of this paper is the simulation of process induced distortion for machined aircraft components to avoid an insufficient quality. The method, presented in this paper, is able to predict qualitative amounts of part distortion caused by process induced residual stresses. A finite element model is utilized which enables the validation of influences of the machining strategy on global shape deviations of the workpiece geometry. An experimental verification is given by  comparing  part distortions caused by a manufacturing process and predicted by the developed simulation. Simulation results demonstrate good agreement between simulated and measured part distortions. At the end of the paper a simulation study is presented which discusses the sensitivity of the simulation for varying machining strategies.