Finite Element Simulation And Experimental Study On Milling Process Of Thin-walled Parts

Thin-walled titanium alloy is widely used in aviation because of its high strength,good corrosion resistance,good mechanical properties,low density and compact structure.Thin-walled parts of titanium alloy are of weak rigidity and high surface accuracy,which are prone to nonlinear and strong time-varying problems associated with material removal in the process of processing,and the heat-force load generated in the process of processing will have a serious impact on the chip formation,tool life and workpiece surface quality.Based on the above problems,three-dimensional finite element simulation is adopted in this paper,and theoretical analysis is combined to carry out the research on the cutting mechanism,tool design and milling parameters in the machining and manufacturing of such parts.The main contents are as follows:First,in finite element simulation,the selection of material constitutive model and the setting of parameters have a crucial impact on the accuracy of simulation results.It is necessary to select the appropriate constitutive equation according to the composition of the material and the situation of use.Therefore,different constitutive models in simulation are analyzed,and Johnson-Cook constitutive equation is selected according to the characteristics and application scope of each model.The stress-strain curves of titanium alloy materials at different temperatures and strain rates were obtained through quasi-static tensile test and SHPB test,and the obtained data were fitted to obtain the constitutive parameters of Ti6Al4 V.Second,using the simulation software of ABAQUS,the realization of the cutter trajectory for the curve of the titanium alloy thin-walled milling process simulation,the workpiece is obtained by post-processing Mises stress nephogram and cutting tool temperature contours and milling force curve,and milling experiment was carried out,the milling force test results compared with the results of simulation and analysis of the causes of error,which verified theestablished model is accurate,lay the foundation for the subsequent simulation study.Again,after selecting milling cutter rake Angle,Angle,spiral Angle and cutting edge radius as the research object,the single factor analysis was carried out on the titanium alloy thin-walled milling process,the different structural changes caused by the milling force,milling temperature,workpiece deformation and knife-change rule and the reasons of the contact length,will receive a range of cutter structure by using the orthogonal experiment,some suitable for processing titanium alloy thin-walled structural parameters of end milling cutter.Finally,the application of genetic algorithm to optimize the milling parameters of MATLAB software,high speed milling machining center,the VDL-1000 E will get the milling parameters are optimized and experience the milling parameters comparison experiment was carried out,which verify the validity of the optimization,the results of the study to improve the surface quality of the surface of titanium alloy thin-walled and provide strong support to improve tool life.