Simulation of Residual Stress Related Part Distortion

Abstract

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 which leads to shape deviations and time consuming repair processes or even scrap. The research objective of this paper is the simulation of distortion caused by residual stress for machined aircraft components to avoid an insufficient quality. The method, presented in this paper, is able to predict the part distortion caused by process induced and initial residual stresses. A custom FEM pre-processing is used which takes the actual machining strategy into account to predict the shape deviations of the machined workpiece. An experimental verification is given by comparing measured part distortions caused by a manufacturing process and predicted by the developed simulation. The Validation is done on a complex structural part. The simulation results show good agreement between simulated and measured part distortions.