Research On Stability Limit And Dynamic Machining Error In The Milling Of Thin-walled Workpiece

High efficiency and high precision machining of thin-walled workpiece has long been a difficult technical problem of research at home and abroad. Mainly because of the poor machining process of thin-walled workpiece, the process of machining is very easy to produce vibration, resulting in the quality of workpiece processing is not up to standard, greatly increased the processing cost. Therefore, only the vibration of the machining process can be avoided effectively, and the high efficiency and precision of the thin-walled workpiece can be realized. In this paper, the typical aluminum alloy thin-walled workpiece as the research object, the thin-walled workpiece flank milling process in the process of dynamic research, the main contents are as follows:1.The forming mechanism of regenerative chatter is described, and the dynamic model and dynamic equation of thin-walled workpiece is established on this basis. By analyzing and solving the stability of the dynamic equation, the stability lobes of the milling are drawn and the influence factors are studied.2.The dynamic characteristics of milling system are established with the change of milling position by using modal experiment. Three dimensional stability of thin-walled workpiece is established and the applicability of the stability diagram is verified. The relationship between the surface topography and the surface topography is established and the three dimensional stability diagram is a reasonable choice for the milling parameters of the thin wall parts, which provides a theoretical basis for the realization of stable milling and improving the machining efficiency.3.The frequency domain analytical expression of dynamic machining error in milling process of thin-walled workpiece is established. The simulation results are obtained. The effect of milling parameters on the surface location error is analyzed. The surface location error of different rotating speed is measured by coordinate measuring machine. The correctness of the theoretical modeling of the surface location error is verified. It provides a theoretical basis for the optimization of milling parameters. Using cutting thickness model of milling cutter tooth profile, the cutting force and displacement in time domain are obtained. The corresponding dynamic error is obtained, including surface location error and milling residual height. The characteristic of milling is obtained using the Poincare map.4.In order to process stability and machining dynamic error, the material removal rate is chosen as the research object, the relationship between radial cutting depth, axial depth and spindle speed is established, and the material removal rate is obtained. The corresponding spindle speed and radial cutting depth are obtained.