Research And Software Development On The Stability Prediction Of High Speed Milling

As an important basic technology, high speed milling has become an important part of the advanced manufacturing technology in the 21st century, which has been widely used in aerospace, automotive, mold, energy, and many other fields. Chatter in milling process is the main constraints of realizing high-speed, efficient and accurate processing high speed milling, so the problem of stability prediction under high-speed milling machining is urgency. Taking the stability prediction of high-speed milling and Chatter as the background, the prediction of high-speed milling stability as object, the dynamic and stability characteristics of spindle and tool system and gyroscopic effect and also that of workpiece in the high speed milling is studied by the method of theoretical analysis and finite element simulation, and some of the results developed by the form of software.Based on the force model of the instantaneous cutting force, the dynamic milling model is established considering two aspects. First, the dynamic model is established considering that the gyroscopic effects of the high speed rotating shaft. Second, the dynamic model is also established considering that the stiffness of workpiece and that of the tool is at the same magnitude.Based on the dynamic model setup, the method of the analytical stability analysis and the stability limit diagram used as a representation of milling stability is proposed, which is the theoretical basis of prediction, evaluation and optimization. Based on two-dimensional stability limit diagram, the establishment of three-dimensional stability limit diagram is studied, by which the direct and clear analysis of milling parameters on milling stability, comprehensive, and accurately selection of the optimal cutting conditions and stability milling parameters can be made.By simplifying the tool system to beam model, the numerical method for solving differential equations is proposed, and the gyroscopic effect of the tool system and its natural frequency is analyzed. By the finite element method, the finite element model of the tool and spindle system is established, gyroscopic effect on the dynamics and stability is analyzed. The finite element model of the workpiece is established, respectively, dynamic characteristics of different conditions and its stability are also analyzed.On the base of achieved method in the stability limit diagram prediction, the software compiler development is proposed, which probes into the the vibration and instability mechanisms, characteristics and evolution discipline of high speed milling and make it easy to apply to actual production and realization of engineering applications.