Suppression of chatter vibration of boring tools using impact dampers

In this study, improvement of the damping capability of boring tools and suppression of chatter vibration were attempted using impact dampers. Bending tests, impact tests and cutting tests were carried out, whilst widely varying the method of applying an impact damper to a boring tool. The effects of the amount of free mass and clearance, the overhang length of boring tools and their cutting condition were investigated. As a result, the following points were clarified. (i) The damping capability of boring tools is considerably improved using impact dampers. (ii) All three types of impact dampers used in the experiment can considerably suppress the vibration of boring tools in the vertical direction (principal force direction), but hardly suppress it in the horizontal direction (thrust force direction) where the amplitude is extremely small. (iii) In practical use, the method of equipping an impact damper on the flank face of a boring tool is desirable. (iv) Using an impact damper, it is possible to bore deeper holes in comparison with boring tools now on the market and to improve the efficiency of boring operations. (C) 2000 Elsevier Science Ltd. All rights reserved.