Research On Milling Sidewall Deformation Of Thin-walled Parts Of Frame Reinforced With Mixed Materials

With the gradual development of China’s aviation industry,in order to meet the needs of modern aircraft in both military and civilian fields,the requirements of aviation parts have gradually moved towards small quality,high precision and high strength,so frame thin-walled parts have become the development direction of aviation parts.However,due to the large amount of material removal during processing,it is affected by milling force,friction and residual stress,which makes it difficult to ensure the processing accuracy,which greatly restricts the development of precision manufacturing.Only by finding a way to reduce and inhibit the processing deformation of frame thin-walled parts can we fundamentally promote the development of the aviation industry.In this paper,the influence of mixed material auxiliary support on the processing deformation of workpiece is explored by combining experiment and simulation,and the effects of dynamic stiffness change and residual stress redistribution on the processing deformation of frame thin-walled parts are explored,and the specific research content is as follows:(1)Firstly,the theoretical analysis of the processing deformation of the workpiece is carried out through the work mutual equality theorem,and then the simulation model is established by the finite element simulation software to carry out the comparative study under the condition of auxiliary support,and finally the deformation suppression effect of auxiliary support technology on the middle rib plate of 7075 aluminum alloy "Japanese" frame thin-walled parts in the milling process is preliminarily verified through experiments.(2)In view of a series of problems existing in the existing auxiliary support materials,this paper compares and analyzes the advantages and disadvantages of compressive strength,curing shrinkage rate and solidification rate under different material ratios by adding other materials such as quartz sand to paraffin-based materials,and obtains the optimal material ratio scheme that meets the requirements,so as to better apply to the auxiliary support of frame thin-walled parts.(3)Aiming at the influence of dynamic stiffness change caused by material removal on the machining deformation of workpiece under the initial residual stress release and dynamic cutting force application state,this paper parametrically marks the model mesh and applies the initial residual stress through python script,and applies the dynamic milling force of the workpiece through the Fortune language,so as to establish a finite element simulation model for dynamic change of residual stress and dynamic removal of materials.(4)In order to explore the influence of filling parameters on the machining deformation of the workpiece,the finite element simulation model is used to compare and analyze the influence of auxiliary support on the shape and numerical size of the deformation curve of the middle rib plate of the workpiece,and verify the reliability of the model through experiments,and explore the change trend of different filling parameters on the inhibition effect of workpiece machining deformation.In this paper,the removal and residual stress redistribution of materials are realized through simulation models,which improves the modeling efficiency and reliability of results,and the proposed auxiliary support materials can better meet the needs of industrial processing.Finally,by establishing the milling processing model under different auxiliary support heights,the influence law of auxiliary support height on the processing deformation of workpiece is obtained,which is of great significance for the processing and production of frame thin-walled parts.