The Mechanism of Chatter Vibration in a Spindle-Workpiece System: Part 3—Analytical Considerations

Chatter vibration occurring in the spindle-workpiece system of a lathe is treated theoretically, considering the phase lag of cutting force and chatter marks, the dynamic variation effects on cutting force of cutting velocity, and the rake angle during vibration. As a result, it is clarified that the chatter vibration is mainly induced by the phase lag of cutting force (primary chatter) and by the phase lag of chatter marks in successive cutting (regenerative chatter). The dynamic variations of the cutting velocity and rake angle make the spindle-workpiece system more unstable under vibration. The effect of cutting velocity variation is more remarkable than that of rake angle in both types of chatter. Chatter vibration can effectively be suppressed by enlarging the damping capacity of the system.