Gabor Stepan教授学术报告会－－Nonlinear cutting forces in machine tool vibrations
发布日期：
2014-08-25
浏览次数：
266
报告题目：Nonlinear cutting forces in machine tool vibrations
报 告 人：Gabor Stepan教授，匈牙利科学院院士，欧洲科学院院士
时 间：2014年8月27日（周三）上午10：00
地 点：芝纶馆308
主办单位：力学与材料学院计算力学所
报告摘要：
The basic modelling issues of machine tool vibrations are reviewed for turning and milling processes. Nonlinear effects in cutting processes described by delay-differential equations result in parameter domains (called bistable or unsafe zones) where stable oscillation (called chatter) occurs together with stable trivial solution (called stationary cutting). A measurement method is proposed to identify the 'size' of this bistable zone as function of one of the relevant cutting parameters, namely the chip thickness. The constant width of this bistable zone corresponds to the classical power law, while a global maximum of the width of this zone refers to the existence of an inflexion in the cutting force characteristics. In the view of the experimental results, the existing formulas for the nonlinear cutting force characteristics are analyzed.
The basic modelling issues of machine tool vibrations are reviewed for turning and milling processes. Nonlinear effects in cutting processes described by delay-differential equations result in parameter domains (called bistable or unsafe zones) where stable oscillation (called chatter) occurs together with stable trivial solution (called stationary cutting). A measurement method is proposed to identify the 'size' of this bistable zone as function of one of the relevant cutting parameters, namely the chip thickness. The constant width of this bistable zone corresponds to the classical power law, while a global maximum of the width of this zone refers to the existence of an inflexion in the cutting force characteristics. In the view of the experimental results, the existing formulas for the nonlinear cutting force characteristics are analyzed.
报告人简介：
Gabor Stepan is a professor at Department of Applied Mechanics, Budapest University of Technology and Economics. He is a member of Hungaryian Academy of Science, a member of European Academy of Science, former Dean of the Faculty of Mechanical Engineering at Budapest University of Technology and Economics. He was a Fulbright Visiting Professor of California Institute of Technology (CalTech), Pasadena in 1994-95. His research fields include delayed dynamical systems, stability theory, and nonlinear vibrations. His is/ was a member of the editorial boards: Journal of Vibration and Control, Journal of Nonlinear Science, Philosophical Transactions of the Royal Society, Mechanism and Machine Theory, Physica D.