数控车削过程再生型颤振稳定性建模与仿真

考虑瞬态切屑厚度变化和刀具角度变化对颤振的影响，基于再生型颤振机理建立了精确实用的数控外圆车削动力学模型.在此基础上应用数字仿真技术开发了车削颤振分析专用软件包，并结合相关试验数据进行了仿真分析.仿真结果表明，极限切宽和主轴转速之间具有明显的非线性关系，且主轴转速对颤振影响最为明显；切削稳定性随主振系统的等效刚度或阻尼比增加而增大，但当方向系数、切削重叠率或切削刚度增加时，稳定性反而降低，同时叶瓣曲线的形状也随之改变；但主振系统固有频率未影响曲线形状，它的增大使曲线整体右移.这为相应抑振措施提供了必要的理论依据.

Modeling and Simulation of Regenerative Chatter Stability in CNC Lathing Process

Taken into account of the variation of the transient chip and cutting angle, a dynamic model was proposed for the ex-circle computerized numerical control (CNC) lathing based on the regenerative chatter theory. By applying digital simulation technique, a software package was developed to do simulations for available experimental data. The simulation results clearly showed the nonlinear relation between the limited cutting width and the spindle speed, and the spindle speed has more effect on the chatter than other factors. The stability increases with increase of the equivalent stiffness or the damping ratio in vibrating system, but it will decline when the directional coefficient, cutting overlapping coefficient or cutting stiffness increases. And the shapes of the lobes are simultaneously changed. However, the natural frequency of the vibrating system has no effect on the shapes of the stability lobes, and the lobes integrally move to the right with its increase. These results provide theoretical basis for chatter suppression.