椭圆轨迹振动切削加工

Journal of Materials Processing Technology 214(2014)2644–2659

Contents lists available at ScienceDirect

Journal of Materials Processing

Technology

j o u r n a l h o m e p a g e :w w w.e l s e v i e r.c o m /l o c a t e /j m a t p r o t e

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Fundamental investigation of ultra-precision ductile machining of tungsten carbide by applying elliptical vibration cutting with single crystal diamond

Jianguo Zhang,Norikazu Suzuki ∗,Yilong Wang,Eiji Shamoto

Department of Mechanical Science and Engineering,Nagoya University,Furo-cho,Chikusa-ku,Nagoya 464-8603,Japan

a r t i c l e

i n f o

Article history:

Received 19November 2013

Received in revised form 30April 2014Accepted 20May 2014

Available online 9June 2014

Keywords:

Elliptical vibration cutting Ductile machining Tungsten carbide

Material composition Tool wear Sculpturing

a b s t r a c t

This paper presents essential investigations on the feasibility of ductile mode machining of sintered tungsten carbide assisted by ultrasonic elliptical vibration cutting technology.It lays out the foundations toward efficient application of elliptical vibration cutting technology on tungsten carbide.Tungsten car-bide is a crucial material for glass molding in the optics manufacturing industry.Its grain size and binder material have significant influence not only on the mechanical and chemical properties but also on the machining performance of tungsten carbide.In order to investigate the influence of material compo-sition on tungsten carbide machining,a series of grooving and planing experiments were conducted utilizing single crystal diamond tools.The experimental results indicated that as compared to ordinary cutting where finished surface deteriorates seriously,ductile mode machining can be attained success-fully by applying the elliptical vibration cutting technique.It was also clarified that the binder material,the grain size,cutting/vibration conditions as well as crystal orientation of the diamond tool have sig-nificant influence on the tool life and the machined surface quality.Based on these fundamental results,feasibility of micro/nano-scale fabrication on tungsten carbide is investigated.By applying amplitude con-trol sculpturing method,where depth of cut is arbitrary changed by controlling the vibration amplitude while machining,ultra-precision textured grooves and a dimple pattern were successfully sculptured on tungsten carbide in ductile mode.

©2014Elsevier B.V.All rights reserved.

1.Introduction

With the rapidly developing optoelectronics industry,demand for advanced manufacturing technology for sophisticated micro/nano structures on optical systems is increasing drastically.For example,glass lenses with small radius and large curvature have been used in various devices to miniaturize their structures and/or to attain large storage capacity.Some micro/nano optical gratings have been used in optical communication equipments,encoders,and digital cameras.In order to realize mass production of those glass devices,tungsten carbide is heavily used in molding because of its unique mechanical,thermal and chemical properties.Ultra-precision cutting has been generally applied to fabricate sophisticated micro/nano structures,and it has been widely used

∗Corresponding author.Tel.:+81527894491;fax:+81527893107.E-mail addresses:nuzhjg@upr.mech.nagoya-u.ac.jp (J.Zhang),

nsuzuki@mech.nagoya-u.ac.jp (N.Suzuki),wang@upr.mech.nagoya-u.ac.jp (Y.Wang),shamoto@mech.nagoya-u.ac.jp (E.Shamoto).

especially for a variety of plastic molding applications.However,application of ultra-precision cutting to brittle materials is limited.Since tungsten carbide is a typically hard and brittle material,its ductile machining is extremely difficult by the ordinary ultra-precision cutting technology due to generations of brittle fracture in the workpiece and excessive tool damage.Bulla et al.(2012)reported the feasibility of ultra-precision diamond turning in ductile mode on binderless,nano crystalline tungsten carbide.However,tool wear is not negligible and thus the cutting area is extremely restricted.In contrast to cutting,ultra-precision grind-ing is applicable to ductile mode machining of tungsten carbide,as reported by Yin et al.(2004).Suzuki et al.(2008)has applied the grinding technology successfully in particular applications.Suzuki et al.(2010)additionally reported that following lapping and/or polishing are also effective to achieve higher quality surface finish.However it is extremely difficult to fabricate sophisticated micro/nano-scale structures especially with sharp edges by these methods.In addition,the conventional ultra-precision grinding operation is generally time-consuming as compared to cutting operation due to its complexity.These facts impose significant

/10.1016/j.jmatprotec.2014.05.0240924-0136/©2014Elsevier B.V.All rights reserved.