Milling Stability Analysis And Parameter Optimization Of Unequal Pitch Cutter

As a very important machining method,milling is widely used in metal material processing and manufacturing industry.The milling precision is affected by many factors,and chatter is a common dynamic instability phenomenon,which seriously affects the machining quality of high-precision parts in milling process.Therefore,it is of great significance to reduce chatter in milling process to improve milling efficiency and accuracy.Based on pitch milling cutter as the research object,using different pitch cutter can reduce the advantages of milling chatter,and through optimizing processing parameters of the milling cutter and cutting tool structure reduce chatter in milling process,improved the milling cutter of the milling tooth pitch,significantly improve the quality of the surface of the processed parts,range of pitch cutter has guiding significance for practical engineering application.The main research contents of this paper are as follows:(1)The reason of chatter phenomenon in milling process was analyzed theoretically,and the milling system dynamics model of unequal pitch cutter was established;The time finite element method(TFEA)was used to solve the motion differential equation of the milling system dynamics model,which laid the foundation for drawing the blade diagram of milling stability with unequal pitch cutter.(2)Several representative points on the blade diagram of unequal pitch milling cutter stability were randomly selected,and the time domain diagram of milling force with time was obtained through the milling experiment,and the frequency domain diagram of milling force was obtained by Fourier transform to judge the actual milling stability under various conditions.The stability of the actual milling process was compared with the stability of the flap diagram obtained by the time-finite element method to verify the accuracy of the time-finite element method.The experimental results show that the 6mm milling cutter with Angle of 85°,95°,85°,95° has better vibration reduction effect in actual slot milling.(3)The accuracy of the time finite element method is verified by milling experiments.First of all,by obtaining the time domain diagram of the corresponding milling force changing with time at several representative working points on the unequal pitch milling cutter stability leaf flap chart,secondly,the stability of the milling system under the working condition is judged by the spectrum,and the stability of the leaf lobe diagram obtained by the time finite element method is compared,and the correctness of the time finite element method is verified: The experimental results show that the 6mm milling cutter with an interdental angle of 85°,95°,85°,95° has a good vibration damping effect in the actual slot milling.(4)On the basis of the previous study on the flutter of the unequal pitch milling cutter,in order to further improve the milling performance of the unequal pitch milling cutter,the BP neural network and genetic algorithm are used to optimize the 12 sets of experimental data obtained by the milling force experiment with the minimum value of the milling force.The results show that under the given constraint conditions,the optimal parameter combination of unequal pitch milling cutter slot milling is 3972.17r/min,milling depth of 1.83 mm,and adjacent interdental angle difference of 6.54°.