| Titanium alloy is widely used in the manufacture of curved parts of aero-engine due to its high specific strength,strong corrosion resistance and stability under high temperature conditions.Efficient,precise and high-performance titanium alloy processing technology has become the key to the aerospace manufacturing industry,and thin-walled curved parts are often used as the key part of the parts,which have high requirements for dimensional accuracy and surface roughness.Due to the weak resistance to elastic deformation of titanium alloy,the springback phenomenon of the tool-chip contact area is common during processing,especially when processing curved thin-walled parts,resulting in violent friction between the flank surface and the cutting surface of the workpiece,which affects the parts Accuracy;due to material properties and external interference,chatter vibration will occur during the processing of thinwalled titanium alloy parts,which will cause great damage to the workpiece.On the other hand,titanium alloy has poor thermal conductivity.In the field of high-speed micro-milling processing,the cutting amount is generally very small,which increases the elastic recovery force of the processed surface material on each cutting edge of the tool,speeds up the tool wear rate,and reduces it.Durability,at the same time,has a certain impact on the formation of cutting heat,which makes the quality of the processed surface worse.This paper focuses on the research on the processed surface quality of TC4 titanium alloy thin-walled curved surface parts.Through simulation and experiment,the influence on the processed surface quality of the material is analyzed from the aspects of cutting force,cutting temperature,and cutting vibration.The main research contents are:(1)Through the analysis of the geometry of the ball-end micro-milling cutter and the influence of the tool eccentricity error,the formula for calculating the instantaneous undeformed cutting thickness is introduced;the basis for judging the participation of the cutting edge micro-element in cutting is established by the micro-element method,and the analysis of the chip's microscopic state Whether it is formed or not,the instantaneous cutting force calculation model is established.(2)In-depth study of the mechanism of regenerative chatter and forced regenerative vibration during the cutting process,the basis for judging the stability of the cutting system is given,and the intuitive stability judgment method is given through the drawn stability diagram.(3)Use Deform-3D finite element analysis software to model and simulate the milling of thin-walled surfaces with a ball-end micro-milling tool,study the law of milling force and temperature changes in the milling of thin-walled surfaces,and analyze the changes in cutting consumption during the process of milling thin-walled surfaces.The effect of the parameter on the cutting force.(4)An experimental study on the milling of Ti6Al4 V thin-walled curved surfaces using a ball-end micromilling cutter with a diameter of 1mm.The influence of cutting parameters on the cutting force and vibration during the milling process was summarized and analyzed.The surface morphology and The measured roughness studies the influence of different milling process parameters on the surface quality.The results show that the heat generated in the cutting process of thin-walled TC4 titanium alloy is mainly concentrated in the tool-chip contact part;the maximum stress of the workpiece during cutting is distributed in the plastic deformation zone,followed by the friction deformation zone;in the study of cutting chatter,The chatter problem of the workpiece is the most serious when the spindle speed is 6000n/min.The three-dimensional topography analysis of the machined surface shows that the spindle speed is 7000r/min,the feed per tooth is 2?m/z,and the milling depth is 0.15 mm.The processing effect is better under the parameters. |
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