Abstract:  Aiming at the problem that chatter often appeared in machining process of the slender aircraft structure, such as stringer structure parts, which lead to poor machining surface quality, and conservative process parameters could easily lead to low machining efficiency, the optimization of high-efficiency milling parameters was carried out. Firstly, the dynamic characteristic parameters of the tool system were obtained according to the hammering test; secondly, the finite element model of the workpiece system under different working conditions was established to analyze the harmonic response and obtain the dynamic characteristics in the process of machining. Then, the chatter stability region of the process system was established by integrating the dynamic characteristics of the tool system and the workpiece system. Finally, the machining efficiency and tool life were established as the objective functions. The parameter optimization model with cutting parameters as variables and cutting stability as the main constraint conditions was obtained by particle swarm optimization algorithm. The experimental results show that the chatter is effectively eliminated by using the optimized cutting parameters, and the processing efficiency can improve by about 19% on average. The method can be used for reference to avoid flutter of slender aircraft structures in the early stage of process preparation.

Key words:  stringer structure parts; dynamic characteristics; cutting parameter optimization; vibration stability