Ultra-Precision Machining of Dies for Microlens Arrays Using a Diamond Cutting Tool

2009 ◽  
Vol 407-408 ◽  
pp. 359-362 ◽  
Author(s):  
Takehisa Yoshikawa ◽  
Masayuki Kyoi ◽  
Yukio Maeda ◽  
Tomohisa Ohta ◽  
Masato Taya
Keyword(s):  
Cutting Tool ◽  
Diamond Tool ◽  
Liquid Crystal Displays ◽  
Precision Machining ◽  
Diamond Cutting ◽  
Microlens Arrays ◽  
Synchronous Control ◽  
Ultra Precision ◽  
Diamond Cutting Tool ◽  
Cutting Unit

Patterning of numerous microlenses on a surface improves the optical performance of components such as liquid crystal displays. A cutting method using a diamond tool is examined to fabricate a molding die that employs arbitrary array patterns to mold millions of microlenses. The present paper investigates machining of microlenses on the order of 2 kHz, using a piezo-actuated micro cutting unit and a synchronous control system of the cutting unit with an NC controller. Experiments using this system revealed that it is possible to machine a large number of microlenses on a molding die with high precision.

Ultra-Precision Cutting of Roll Die with Micro Lens Arrays for Plastic Film

2011 ◽  
Vol 325 ◽  
pp. 563-569 ◽  
Author(s):  
Takehisa Yoshikawa ◽  
Masayuki Kyoi ◽  
Hideaki Onozuka ◽  
Hideaki Tanaka ◽  
Yukio Maeda ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Control System ◽  
Diamond Tool ◽  
Liquid Crystal Displays ◽  
Plastic Film ◽  
Synchronous Control ◽  
Machining System ◽  
Ultra Precision ◽  
Micro Lens ◽  
Cutting Unit

Patterning vast numbers of micro lenses on a surface increases technical importance to improve characteristics of optical parts such as liquid crystal displays. A cutting method using a diamond tool is examined to make a molding die by which array patterns of many micro lenses are molded. Realizing the cutting procedure, the developed machining system employs a cutting unit actuated by PZT and a synchronous control system of the cutting unit with a NC controller. The present paper investigates machining of micro lenses on the order of 2 kHz, using a piezo-actuated micro cutting unit. Experiments using this unit revealed that it is possible to machine a large number of micro lenses on a molding roll die for plastic film with high precision.

A study of the ultra-precision truing method for flank face of round nose diamond cutting tool

2017 ◽  
Vol 30 ◽  
pp. 124-132 ◽  
Author(s):  
Ning Yang ◽  
Wenjun Zong ◽  
Dong Wu ◽  
Zengqiang Li ◽  
Tao Sun
Keyword(s):  
Cutting Tool ◽  
Diamond Cutting ◽  
Ultra Precision ◽  
Flank Face ◽  
Diamond Cutting Tool

Study of the Mechanism of Groove Wear of the Diamond Tool in Nanoscale Ductile Mode Cutting of Monocrystalline Silicon

2006 ◽  
Vol 129 (2) ◽  
pp. 281-286 ◽  
Author(s):  
M. B. Cai ◽  
X. P. Li ◽  
M. Rahman
Keyword(s):  
Cutting Tool ◽  
Diamond Tool ◽  
Monocrystalline Silicon ◽  
Diamond Cutting ◽  
Workpiece Material ◽  
Hard Particles ◽  
Ductile Mode ◽  
Ductile Mode Cutting ◽  
Flank Face ◽  
Diamond Cutting Tool

In nanoscale ductile mode cutting of the monocrystalline silicon wafer, micro-, or nanogrooves on the diamond cutting tool flank face are often observed, which is beyond the understanding based on conventional cutting processes because the silicon workpiece material is monocrystalline and the hardness is lower than that of the diamond cutting tool at room temperature. In this study, the mechanism of the groove wear in nanoscale ductile mode cutting of monocrystalline silicon by diamond is investigated by molecular dynamics simulation of the cutting process. The results show that the temperature rise in the chip formation zone could soften the material at the flank face of the diamond cutting tool. Also, the high hydrostatic pressure in the chip formation region could result in the workpiece material phase transformation from monocrystalline to amorphous, in which the material interatomic bond length varies, yielding atom groups of much shorter bond lengths. Such atom groups could be many times harder than that of the original monocrystalline silicon and could act as “dynamic hard particles” in the material. Having the dynamic hard particles ploughing on the softened flank face of the diamond tool, the micro-/nanogrooves could be formed, yielding the micro-/nanogroove wear as observed.

scholarly journals Graphitization Behavior of Single Crystal Diamond for the Application in Nano-Metric Cutting

2018 ◽  
Vol 14 (5) ◽  
pp. 377-383 ◽  
Author(s):  
Qingshun Bai ◽  
Zhiguo Wang ◽  
Yongbo Guo ◽  
Jiaxuan Chen ◽  
Yuanjiang Shang
Keyword(s):  
Molecular Dynamics ◽  
Single Crystal ◽  
Cutting Tool ◽  
Diamond Tool ◽  
Diamond Crystal ◽  
Dynamics Simulation ◽  
Diamond Cutting ◽  
Single Crystal Diamond ◽  
Ring Method ◽  
Diamond Cutting Tool

Background: Graphitization behavior of diamond has received an increasing interest in nanoscale machining of some hard and brittle materials. Diamond has always been an important and excellent tool material in cutting area. However, the graphitization of the diamond tool is inevitable when it was used in special conditions. It is indicated that the graphitization of diamond crystal has great influence on the wear resistance of diamond cutting tool. The graphitization behavior needs to be investigated extensively in nanoscale with an atomic view. Molecular dynamics simulation provides a useful tool for understanding of the graphitization mechanism of diamond. The investigation on graphitization behavior of single crystal diamond can also provide a useful reference for the application of diamond cutting tool. Materials and Methods: In this paper, a molecular dynamics (MD) diamond crystal model is built to examine the graphitization behavior of diamond under various conditions. The sixfold ring method was employed to identify the structural characteristics of graphite and diamond. The effects of temperature and crystal orientation on the graphitization of diamond have been revealed. Considering the effect of temperature, the anisotropy of diamond graphitization against various crystal planes is presented and discussed carefully. The nano-metric cutting model of diamond tool evaluated by the sixfold ring method also proves the graphitization mechanisms in atomic view. Results: Results indicate that the sixfold ring method is a reliable method to evaluate the graphitization behavior of diamond crystal. There exists a critical temperature of the graphitization of diamond. The results also show that {111} plane is more easy to get graphitization as compared with other crystal planes. However, {100} plane of diamond model presents the highest antigraphitization property. Conclusion: The obtained results have provided the in-depth understanding on the wear of diamond tool in nano-metric machining and underpin the development of diamond cutting tool.

Cutting performance study of synthetic diamonds tools applied in ultra-precision machining of copper

2020 ◽  
pp. 2150067
Author(s):  
Ning Chen ◽  
Guoqing Zhang ◽  
Menghua Zhou ◽  
Gang Xu ◽  
Yong Li ◽  
...  
Keyword(s):  
Cutting Tools ◽  
Precision Machining ◽  
Performance Study ◽  
Diamond Cutting ◽  
Synthetic Diamonds ◽  
Diamond Cutting Tools ◽  
Ultra Precision ◽  
Study Type ◽  
Tools Wear ◽  
Diamond Cutting Tool

In this study, type Ib, type IIa, and type IIb synthetic diamonds tools were used for the ultra-precision machining (UPM) of copper. Raman spectroscopy showed that the diamond cutting tools used in these experiments exhibited high-quality sp3 structure and little residual stress in the diamond lattice. Type IIb diamond cutting tools showed higher durability and better UPM performance than the other types of diamond cutting tools. Chemical wear was deemed significant with respect to the cutting tools’ wear in this UPM experiment. Higher durability and enhanced UPM performance could be attributed to the higher thermal and chemical stabilities of the type IIb diamond cutting tool.

Microtexture Generation Using Controlled Chatter Machining in Ultraprecision Diamond Turning

2015 ◽  
Vol 3 (2) ◽  
Author(s):  
Syed Adnan Ahmed ◽  
Jeong Hoon Ko ◽  
Sathyan Subbiah ◽  
Swee Hock Yeo
Keyword(s):  
Cutting Tool ◽  
Cutting Speed ◽  
Diamond Turning ◽  
Diamond Cutting ◽  
Machined Surface ◽  
Excited Vibration ◽  
Mass And Heat Transfer ◽  
Tool Shank ◽  
Diamond Cutting Tool

This paper describes a new method of microtexture generation in precision machining through self-excited vibrations of a diamond cutting tool. Conventionally, a cutting tool vibration or chatter is detrimental to the quality of the machined surface. In this study, an attempt is made to use the cutting tool's self-excited vibration during a cutting beneficially to generate microtextures. This approach is named as “controlled chatter machining (CCM).” Modal analysis is first performed to study the dynamic behavior of the cutting tool. Turning processes are then conducted by varying the tool holder length as a means to control vibration. The experimental results indicate that the self-excited diamond cutting tool can generate microtextures of various shapes, which depend on the cutting tool shank, cutting speed, feed, and cutting depth. The potential application of this proposed technique is to create microtextures in microchannels and microcavities to be used in mass and heat transfer applications.

Cyclic shear angle for lamellar chip formation in ultra-precision machining

2020 ◽  
Vol 234 (13) ◽  
pp. 2673-2680 ◽  
Author(s):  
Shaojian Zhang ◽  
Pan Guo ◽  
Zhiwen Xiong ◽  
Suet To
Keyword(s):  
Chip Formation ◽  
Diamond Tool ◽  
Orthogonal Cutting ◽  
Rake Angle ◽  
Shear Angle ◽  
Precision Machining ◽  
Cyclic Shear ◽  
Intrinsic Mechanism ◽  
Classical Models ◽  
Ultra Precision

Shear angle is classically considered constant. In the study, a series of straight orthogonal cutting tests of ultra-precision machining revealed that shear angle cyclically evolved with each lamellar chip formation, i.e. cyclic shear angle. It grew up from an initial shear angle of 0° to a final shear angle 90°- α ( α: tool rake angle) and underwent a series of transient shear angles like classical shear angles and a critical shear angle. The critical shear angle is the sum of the half of the tool rake angle and the characteristic shear angle determined by material anisotropy without the friction effect. Moreover, a new model was developed. Further, a series of face turning tests of ultra-precision machining verified that the cyclic shear angle was the intrinsic mechanism of cyclic cutting forces and lamellar chip formation to induce twin-peak high-frequency multimode diamond-tool-tip vibration. Significantly, the study draws up an understanding of shear angle for the discrepancy among the classical models.

Sign in / Sign up

Export Citation Format

Share Document