Research On Process Parameter Optimization And Process Knowledge Base Technology For Thin-walled Blade

With the development of manufacturing technology in China,the importance of military aerospace products is also increasing.Titanium alloy thin-walled parts due to its light weight,high relative strength,large bearing capacity,good fracture toughness and other significant advantages,the overall performance is superior,in the key complex parts occupy a lot of proportion.Thin-walled structural parts represented by aeroengine blades have the characteristics of thin wall,irregular shape,poor rigidity and high machining accuracy.In the process of precision machining,with the removal of a large number of materials,under the action of milling load,the deformation of products can not meet the requirements of precision,and seriously affect the assembly performance of products.In this paper,the machining deformation and process parameter optimization method of complex thin-walled blade in fiveaxis milling process were studied.Combined with finite element simulation,the machining deformation of complex thin-walled blade was predicted by considering the action of cutting force in the machining process.Local structure stiffness analysis was carried out on the parts at the same time,finds the existing problems of the processing technology,through the establishment of complex parts processing process knowledge base,comprehensive optimization of parts processing technology parameters,realize high precision cutting of parts,ensure the parts machining accuracy,improve the efficiency of parts processing,to implement adaptive precision nc machining.The research content of this paper is summarized as follows.(1)considering the cutting tool position change and blade surface characteristics,through the theoretical analysis and the cutting force experiment set up five axis machining milling force model of complex surface,puts forward the local structural stiffness under the condition of dynamic change of thin-walled parts processing and deformation analysis method,in the process of thin-walled parts processing by the cutting force and the macroscopic elastic deformation and error analysis.(2)For typical thin-walled blade milling process,a finite element prediction model of machining deformation was established.Milling simulation and machining deformation prediction of thin-walled blade were completed based on ABAQUS secondary development.Milling force loading along the tool path was realized by establishing cutter point cycle.The deformation of the selected blade nodes was predicted and the stiffness model was solved,and the deformation law of blade milling was analyzed according to the simulation results.(3)In terms of process parameter optimization,error analysis technology based on cutting force model is based on milling force modeling and simulation deformation prediction.According to different machining processes adopted different milling process parameters optimization strategy,the blade rough machining,the optimization method based on constant material removal rate,to finish the processing parameter optimization based on milling force control,on the basis of the preliminary optimization of quadratic optimization,is the best performance of cutting tool and machine tool at the same time,reduce the mechanical damage,and ensure the machining accuracy of parts at the same time,Improve processing efficiency.(4)For the thin-walled blade processing process,the establishment of a process knowledge base system can be more intelligent process parameters optimization,the development of relevant validation experiments,the finite element prediction results of thinwalled blade milling deformation and cutting parameter optimization method verified the reliability and accuracy of the optimization method.