Residual Stress Evaluation And Deformation Prediction Of Pre-stretched Aluminum Alloy Plate

Aluminum alloy is one of the most commonly used materials in aerospace manufacturing.Because of its light weight,and high strength,the aluminum alloy pre stretched plate is largely used in the manufacture of frame structure and thin-walled structure,etc.However,in the process,the residual stress in the aluminum alloy pre stretched plate is released with the removal of the external material.In this paper,aluminum alloy pre stretched plate was researched in the finite element simulation and cutting test to evaluate the residual stress of plate.The distribution of the residual stress was put in the finite element software for deformation prediction.The finite element software was developed to improve the calculation efficiency of physical simulation and deformation prediction.Finally,it is applied to predict the deformation.The major research works are listed as follows:Firstly,the residual stress of plate is measured using the blind hole method and profile method.In order to improve the measurement accuracy,according to the special requirements of the residual stress measurement of contour method,the effects of wire cutting parameters on the cutting quality of contour method are studied by using Plackett-Burman and orthogonal test method which reveal wire feed rate,wire tension and peak current are three main factors of measurement accuracy.When the peak current of 10 A and 20 g for wire tension and wire feed rate is 180mm/min,the cutting quality is optimal;According to response surface analysis,the prediction model of surface roughness was made to improve the accuracy of contour method.Secondly,for the large size of the structure,it is hard to accomplish the prediction of machining distortion for large-thin-walled titanium alloy complex structures to be used finite element analysis for its sophisticated cutting tool path and entire dimensions.To solve this problem,based on ABAQUS and secondary development,a method made up multi-static implicit analysis steps is proposed to predict machining distortion in the cutting process.The software has been developed,which can be applied to the residual stress and the displacement and stress data of the subsequent analysis.Thirdly,based on the measured residual stress of the pre-stretched plate,the machining deformation was predicted by using the second-developed finite element simulation technology.The simulation results were compared with the cutting test results,and the characteristics of the deformation were obtained.