薄壁零件铣削三维颤振稳定性建模与分析

以低刚度薄壁零件为研究对象,基于加工原理建立精确的铣削过程薄壁零件三维动力学模型,并在此基础上采用全离散解析法对颤振稳定域叶瓣图进行仿真分析及实验验证.结果表明:薄壁零件铣削加工系统的动态特性决定其动力学模型,铣削加工过程主轴转速与颤振临界轴向切削深度之间存在非线性关系,主轴转速对颤振稳定性影响较明显.当系统模态质量、阻尼比及固有频率增大时,颤振稳定性相应加强,同时叶瓣图形状分布随之改变.该理论模型对薄壁零件铣削加工过程切削参数的合理选择,表面加工质量和加工效率的提高具有一定指导意义.

Modeling and Analysis for 3D Chatter Stability of Thin-Walled Parts in Milling Process

In view of the thin-walled part with low stiffness， the 3D dynamics model in milling process was built on the machining principle. The chatter stability lobes were predicted using the full-discretization method and validated by the experiments. The results showed that dynamic characteristics of the thin-walled part in milling process determine the dynamics model. There is the nonlinear relation between the limited cutting depth and the spindle speed， and the spindle speed has more effect on the chatter stability than other factors. When the modal mass， relative damping and natural frequency increased， the stability intensifies and the shape of lobes is changed simultaneously. The theoretical model provides the guidance for reasonable selection of cutting parameters and improvement of machined surface quality and machining efficiency.