细长轴切削颤振的稳定性分析和实验研究

为了对细长轴的加工颤振进行稳定性研究，在对细长轴切削颤振机理的研究基础上，建立了刀具和细长轴耦合振动的两自由度系统的再生型颤振分析模型。利用解析法对时滞的动力学方程进行稳定性分析，得出了关于切削宽度和转速的稳定性切削极限图。从结果中可以得出两自由度系统的极限切削宽度比单自由度系统减小了28.6%。该成果可以为柔性零件的高效稳定加工提供理论切削参数。在车铣复合中心上进行了细长轴的切削颤振实验，通过与稳定性极限图的对比，发现实验结果与理论研究相吻合，并且总结出颤振发生前后刀具和细长轴的振动特性变化规律。这种振动特征的变化过程是对加工颤振进行监测和预警的重要识别指标

Stability analysis and test for cutting chatter of a slender shaft

To study the stability of chatter while cutting a slender shaft,based on chatter mechanism studying of cutting a slender shaft,the analysis model of regenerative chatter was established,for a two-DOF coupled vibration system of a tool and a slender shaft.The stability of the dynamic equations with time delay was analyzed using an analytical method to get a stability cutting limit figure between cutting width and rotational speed.The figure showed that the limit cutting width of the two-DOF system is reduced by 28.6% compared to that of single-DOF system.This result could provide theoretical cutting parameters for highly effective and stable processing of flexible workpieces.The cutting chatter tests of a slender shaft were done in a turn-milling center.Compared with the stability cutting limit figure,the test results agreed well with the theoretical ones.The varying laws of the vibration features of the tool and the shaft during chatter were summarized.They were the important recognition indices when monitoring and early-warning cutting chatters.