Development of a frictionally damped boring bar for chatter suppression in boring process

A novel boring bar was developed for chatter reduction of machining processes. By proposing an internal frictional damping structure, additional energy dissipation during bending vibrations was imposed to the boring bar. The structure consisted of some pins longitudinally press-fitted inside the boring bar. This structure resisted against bending of the boring bar during machining processes. After introducing the structure, an analytical model was presented to determine the amount of energy dissipated by the damper. Using the analytical model and finite element modeling (FEM), the most effective configuration was obtained for the proposed frictional damper structure. After determining the best configuration, a damped boring bar specimen was fabricated for experimental comparison with a regular boring bar. The modal and cutting tests were performed on the specimens. The modal test revealed a significant increase in the structural damping of the boring bar. The cutting tests were performed at different depths of cut and different spindle speeds, and the process was investigated through sound analysis and surface finish observation. Experimental comparisons indicated the higher performance of the proposed tool.

Automated summary

A novel boring bar was developed with an internal frictional damping structure to reduce chatter in machining processes. Experimental comparisons showed that the proposed tool exhibited higher performance in modal and cutting tests compared to a regular boring bar.