Chatter stability prediction in high-speed micromilling of Ti6Al4 Vvia finite element based microend mill dynamics  

作　　者：Kundan K. Singh Ramesh Singh 

机构地区：[1]Department of Mechanical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India

出　　处：《Advances in Manufacturing》2018年第1期95-106,共12页先进制造进展（英文版）

摘　　要：High-speed micromilling （spindle speeds 100 000r/min） can create complex three-dimensional microfeaturesin difficult-to-machine materials. The micromachined sur-face must be of high quatity, to meet functional require-ments. However, chatter-induced dynamic instabilitydeteriorates the surface quality and can be detrimental totool life. Chatter-free machining can be accomplished byidentifying stable process parameters via stability lobe dia-gram. To generate accurate stability lobe diagram, it isessential to determine the microend mill dynamics. Fre-quency response function is required to determine the tool-tip dynamics obtained by experimental impact analysis.Note that application of impact load at the microend mill tip（typically 100 - 500 μm） is not feasible as it would invari-ably end with tool failure. Consequently, alternative meth-ods need to be developed to identify the microend milldynamics. In the present work, the frequency responsefunction for the microend mill is obtained by finite elementmethod modal analysis. The frequency response functionobtained from modal analysis has been verified from theexperimentally obtained frequency response function. Theexperimental frequency response function was obtained byimpacting the microend mill near the taper portion with animpact hammer and measuring the vibration of the tool-tipwith a laser displacement sensor. The fundamental fre-quency obtained from finite element method modal analysisshows a difference of 6.6% from the experimental funda-mental frequency. Microend mill dynamics obtained fromthe finite element method is used for chatter prediction inhigh-speed micromilling operations. The stability lobe dia-gram predicts the stability boundary accurately at 60 000r/min and 80 000 r/min; however, a slight deviation isobserved at 100 000 r/min.

关 键 词：Chatter MICROMILLING Microend milldynamics Frequency response function Finite elementmodal analysis 

分 类 号：TB2[一般工业技术—工程设计测绘]