Machining performance of boring processes is often limited by chatter vibration when the boring bar is with a large slenderness ratio. The dynamic vibration absorber (DVA) is the most widely used damper in practical chatter control of boring bars. The DVA consists of an additional mass-spring-damper subsystem and needs accurate tuning of its natural frequency and damping ratio to match the main structure. Compared with the DVA, the friction damper consisting of a mass attached to the boring bar through a sliding interface near the tool insert is more simple and easy for design and implementation. The main purpose of this paper is to model the friction damper and investigate its chatter suppression effect. A mathematical model is established to depict the friction force at the friction interface between the damper body and the main structure. Based on the modeling of the fundamental principle of the friction, the dynamic behavior and machining stability of the friction damper damped boring system can be predicted and analyzed. Parameter studies are also carried out using the numerical model to evaluate the machining stability improvement by using the friction damper and identify the best configuration to maximize the boring stability.
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