Research On The Theory And Experiment Of Boring Bar Based On Friction Damper

The machining stability of the machine tool is the key factor of autoimmunization and intellectualization. An intensive and relative vibration between the cutting tool and work piece occurs during process of the boring,and the chatter would decrease the surface quality and the life of tools. Especially in the deep-hole machining, the chatter occurs easily because of the great ratio of length and diameter. This paper introduced the friction damper in boring bar to depress the chatter, and the result is effective.Firstly, this paper reviews the research work of chatter control technique for boring bar at home and abroad, and introduces the characteristic of different methods. Furthermore, the future research direction of chatter control technique for boring bar is viewed. The theory of cutting stability and the mechanism of chatter are expatiated and the paper also reviews different field of the friction damper was applied. Subsequent researches concentrate on the friction dissipation mechanism in boring bar. A dynamics model about boring was established based on nonlinear friction damper and the parameters investigated are the mass of the subsystem and friction force of the boring bar, then approaches the effectiveness of chatter depression.Secondly, based on friction damper a new boring bar is designed, and explains its work mechanism. The hammer modal experimental research hereby focuses on the influence of dynamic characteristics in different friction condition. Associates with the theory of cutting stability and the mechanism of chatter, analyzes the effectiveness of chatter depression in different friction condition. Furthermore, to validate the practicability of the new boring bar, a cutting experimental research was performed and approaches the accordant results with the hammer modal experiment.Finally, by contrasts the experimental finding and theoretical simulation, there is sliding friction status and adhesive status for a given friction damper. It is found that the optimum value of the friction force that maximizes energy dissipation is constant which make the system be in the critical status between sliding and adhesive. According the cutting experimental research, the friction damper is effective for boring tools.