Analysis Of Establishing Cutting Slip-line Field Based On Matrix Operator

Cutting model analysis is an important step in developing new cutting technology.In the cutting model,most researchers use the mean friction coefficient to analyze the cutting process,while the friction coefficient changes from the change of contact normal stress and temperature in the actual cutting process.Therefore,according to the variable friction coefficient model of the chip contact surface,the matrix operator method is used to establish the cutting slip-line field to analyze the cutting process of GH4169 nickel base alloy.In addition,the accuracy of cutting finite element simulation depends on the constitutive model,contact model and fracture criterion of the material.In the absence of experimental comparison,it is difficult to judge whether the simulation results of cutting finite element are accurate.Therefore,this paper uses the method of mutual verification between slip line field model and cutting finite element simulation to ensure the effectiveness of the analysis results.The specific research contents are as follows:(1)A variable friction coefficient model varying from the contact position is established on the chip contact surface;According to the friction boundary conditions on the chip contact surface,the cutting slip line field is established by using the matrix operator method;The cutting shear angle is calculated by Oxley shear theory,and geometric constraints are added to the slip line field.(2)GH4169 cutting finite element simulation is established,and the corresponding slip-line field is established based on the chip thickness of cutting finite element simulation.The change law of slip line angle with cutting conditions is analyzed,and the differences between slip line fields under different cutting conditions are studied.(3)According to the cutting slip line field,the normal stress of the chip contact surface is analyzed,the chip contact length,cutting force and chip curl radii are predicted,and the differences between them and the finite element simulation results are compared.(4)The orthogonal cutting experiment of GH4169 nickel base alloy was carried out to verify the prediction of chip curl radius by cutting slip-line field and cutting finite element simulation.In general,the chip contact length,cutting force and chip curl radius of the slip-line field are approximately similar to the simulation results,and the error is within an acceptable range.In the orthogonal cutting experiment of GH4169,the curl radius of the experimental chip is consistent with the trend predicted by the two cutting models.Therefore,the analysis results of the two cutting models can provide a reference for the machining of GH4169 nickel base alloy.