切削颤振的相位特性研究

Study on the Phase Characteristics of Cutting Chatter

基于切削颤振动力学模型 ,分析了切削颤振的相位特性—工件前后两转切削颤振信号间相位差在颤振建立过程中的变化特征。结果表明 ,随着颤振的产生 ,该相位差由无序状态逐渐过渡到相对稳定的状态 ,并且相位差在颤振产生初期就已经相对稳定。同时对相位差的在线测试方法也进行了深入的研究。结果表明 ,利用等工件转角间隔采样通过互功率谱密度方法可以实现相位差的精确在线测试。

The phase characteristics of cutting chatter—the changing regularity of the phase shift angle between the chatter signals of two successive cuts are analyzed based on the dynamic model of cutting chatter. The results show that the phase shift angle transits from random state to a relatively stable along state with the formation process of cutting chatter and the phase shift angle becomes stable in the early stage of cutting chatter growth. The method of on-line measuring the phase shift angle is also studied in depth. The results show that the phase shift angle can be measured accurately based on the cross-spectrum method with equivalent interval sampling of workpiece rotary angles. The experiments to verify the phase characteristics of cutting chatter are conducted.