Study On Surface Morphology Of Cutting Titanium Alloy By Shoulder Milling Cutter Under Vibration Action

Titanium alloy materials are widely used in aerospace and other fields because of their excellent physical and chemical properties.Titanium alloy is a typical difficult material,its elastic modulus is small,its thermal conductivity is poor,its stability in cutting process is low,the vibration of tool and workpiece is obvious,and the contact relationship between tool and workpiece is changed at any time,resulting in the machining.The surface morphology distribution is less consistent.To become a bottleneck that restricts the further improvement of the surface quality of the processing.In view of the above problems,this paper is supported by the National Natural Science Foundation project "Non-linear friction dynamic wear multiscale coupling mechanism of high-energy milling cutter(51875145)" and the enterprise cooperation project of Chengdu Aircraft Industry(Group)Co.,Ltd."Large titanium alloy structure parts milling tool life accurate control technology".The surface morphology of cutting titanium alloy by shoulder milling cutter under vibration action was studied.To investigate the influence of milling vibration on the surface morphology of titanium alloy,a square shoulder milling cutter with a diameter of 25 mm was used for cutting titanium alloy.The parameters of the surface morphology of titanium alloy are extracted under different cutting strokes,and the changes of the average deviation of the machining surface contour,the ten-point height of the microstructure and the average spacing of the microstructure along t he direction of the milling cutter are analyzed.To construct the milling vibration behavior sequence and the machining surface morphology distribution behavior sequence,an improved grey correlation analysis algorithm is used to reveal the influence characteristics of milling vibration on the machining surface morphology of titanium alloy.Aiming at the nonlinear random variation of milling vibration and machining surface morphology,the time series of milling vibration and machining surface morphology feature parameters was analyzed by using Gaussian process regression method based on the experimental results of cutting titanium alloy by Square shoulder milling cutter.The Gaussian process model of the surface morphology of milling vibration is constructed,and the vibration acceleration,vibration displacement and standard deviation of milling cutter feed,milling depth and milling width are quantitatively described.The influence of the average arithmetic deviation,the ten point height of the microstructure and the average distance of the surface morphology of milling machining.Through the cutting of titanium alloy by the square shoulder milling cutter,the effects of milling width and tooth error on the surface wear,milling vibration,and surface morphology of the machining teeth are analyzed,and nonlinear surface morphology of the machining surface are studied.Based on the experimental verification,the complex nonlinear characteristics of machining surface morphology under multi-factor synthesis are revealed.The model is provided for milling width,cutter tooth error design,cutter surface wear and milling vibration control.In order to effectively control the surface morphology of milling titanium alloy,the surface morphology characteristic parameters and their distribution consistency are the design goals,milling parameters and cutter teeth error are the process control variables,and cutter tooth wear and milling vibration are the constraints.the process design method of milling titanium alloy is put forward,and the experimental verification is carried out.The results show that compared with the original process,the model and method obtained above reduce the surface morphology characteristic parameters,improve the distribution consistency and improve the surface morphology of milling titanium alloy.