Attenuation of vibration in boring tool using spring controlled impact damper

Abstract

In boring process due to larger overhanging length of tool holder, tool vibration is considered as a significant factor which results in poor surface finish, noise generation, accelerated tool wear and reduced life period of machine tool. This tool vibration is a result of interaction between metal cutting process and the dynamics of machine tool. In order to reduce tool vibration it is necessary to develop suitable mechanisms which will in-turn increase the productivity in manufacturing industries. This investigation aims at analyzing the tool holder with impact damper on tool vibration during boring of hardened AISI4340 steel using hard metal insert with sculptured rake face. Impact damper used in this study consists of a concentrated mass of predetermined size and shape mounted on the tool shank at a specific location by means of springs. Material of impact damper and the location of the damper on the tool shank for achieving effective damping was determined by using computational analysis. When the damper was mounted on the tool shank, its vibration characteristics got altered and provided an inherent damping capability to the tool holder by suppressing tool vibration. Experimental work was carried out to study the influence of impact damper on tool vibration and cutting performance. From both computational and experimental results, it was observed that tool vibration was reduced effectively when impact damper was embedded with tool holder.