Simulation On Deflection Of Aeronautical Thin-wall Workpiece By FE Model

Monolithic thin-wall workpieces are widely used as structures of aircraft for the sake of strength ratio improvement. However, due to the low-rigidity of the workpieces, deflection errors induced by cutting force cause a common problem that influences significantly the accuracy and the surface quality. Deflection of thin-wall workpiece in machining process has been providing a serious challenge for engineers. Therefore, it has great academic and engineering value for the prediction of the deflection of thin-wall workpiece.Firstly, the process of milling aerospace material (aluminum alloy 7075-T7451) was simulated by the three dimension dynamic FE model. Meshing technology, material constructive model, definition for friction between the flute and the material and chip separation criteria were fully studied. Based on the simulation of milling aluminum alloy by FE model, the values of three components of milling force, the morphology of chip and the and the distribution of stress were obtained. In addition, the FE model was validated through the milling experiments.Secondly, in order to promote the speed of FE calculation under the prerequisite of guaranteeing the simulation precision, the simplifying methodology of"quasi-dynamic simulation"was proposed. The deflection of cantilever plate during peripheral milling process was fully analyzed by this method, in addition, a set of milling experiments were arranged to validate the methodology.Finally, by the"quasi-dynamic simulation"method which was validated by experiments and analysis of the processing technology for thin-wall workpiece, the machining deflection of monolithic thin-wall workpiece was predicted by the 3-D dynamic model with the methodology of"quasi-dynamic simulation"...