Mechanical Molding And Stability Analyze For The Milling Process Of Thin-walled Work-piece

The fuel container of rocket is a kind of large-sized thin-walled work-piece,which tends to vibrate in processing,because of its poor stiffness,and that could low the efficiency and quality of the processing.Because of that limit,the processing of the thin-walled work-piece has been one of the main issues researched those years.In this paper,a model of three-dimensional milling force and stability analytical model adapted for thin-walled work-piece are proposed.The test for FRF of cutter tip is showed.The influence of modal parameters on the milling stability is analyzed by simulation method.The main work contains:(1)Based on the theory of orthogonal cutting and three-dimensional infinitesimal oblique cutting theory,and shear deformation theory and friction theory,it’s deduce that the expression of milling force with geometry of the cutter,shear angle,frictional angle,and yield limit of the cutting material.(2)Considering the thin-walled characteristics of the work-piece,a dynamic model is established for analyzing milling stability mainly concluding characteristic of the cutter and work-piece in vertical cross-section.For the three-dimensional analysis,the characters in axial direction are concluded additionally.The stability limit is solved out by solving the equation between cutting force and system characteristic in frequency domain.(3)The FRF test,which is obtained by processing the input and output signal,is showed,and the test result is analyzed.(4)Based on the result of test,using simulation method,it’s analyzed that the relationship between modal parameters and stability,in which the parameters conclude inherent frequency,stiffness and damping ratio.