scholarly journals Electrical Discharge Machining for Sintered Polycrystalline Diamond using Bipolar Pulse Generator

2019 ◽  
Vol 53 (134) ◽  
pp. 200-206
Author(s):  
Hisashi MINAMI ◽  
Koji WATANABE ◽  
Kiyonori MASUI
Keyword(s):  
Electrical Discharge ◽  
Pulse Generator ◽  
Electrical Discharge Machining ◽  
Polycrystalline Diamond ◽  
Bipolar Pulse

Electric discharge milling of polycrystalline diamond

1997 ◽  
Vol 211 (8) ◽  
pp. 643-647 ◽  
Author(s):  
Y H Liu ◽  
Y F Guo ◽  
J C Liu
Keyword(s):  
Surface Area ◽  
Electric Discharge ◽  
Electrical Discharge ◽  
Pulse Generator ◽  
Electrical Discharge Machining ◽  
Polycrystalline Diamond ◽  
Large Surface Area ◽  
Lower Efficiency ◽  
Pulse On Time ◽  
Electric Discharge Milling

Polycrystalline diamond (PCD) has been used widely in modern industry. However, the manufacture of PCD blanks is not an economical and efficient process. The shaping of PCD blanks with conventional machining methods (such as grinding), is a long, labour-intensive and costly process. Electromachining processes promise to be effective and economical techniques for the production of tools and parts from PCD blanks. Wire electric discharge machining is able to effectively slice PCD. Electrical discharge machining (EDM) and electrical discharge grinding (EDG) shape PCD blanks at a lower cost. However, EDM and EDG of a large surface area on PCD show lower efficiency. This paper presents a new process of machining PCD using electrical discharge (ED) milling. ED milling employs a DC source instead of the pulse generator used in EDM, and uses a water-based emulsion as the machining fluid. This process is able to effectively machine a large surface area on PCD, and effectively machine other advanced conducting materials such as cubic born nitride (CBN), and ceramics. The effect of pulse on-time, peak current, and polarity on the process performance has been investigated.

A Truing Technique of Flattening Diamond Grains for Fabricating Microstructures with Fine Surfaces

2008 ◽  
Vol 389-390 ◽  
pp. 350-355
Author(s):  
Takeshi Harada ◽  
Takuya Semba
Keyword(s):  
Surface Roughness ◽  
Electrical Discharge ◽  
Diamond Tool ◽  
Electrical Discharge Machining ◽  
Polycrystalline Diamond ◽  
Mesh Size ◽  
Diamond Disk ◽  
Working Surface ◽  
Work Material ◽  
Tool Profile

A truing technique that can be used to shape the tip of an electroformed diamond tool into a hemisphere and flatten diamond grains on the tool working surface at the same level as the bond face was developed. A polycrystalline diamond disk whose top surface roughened by electrical discharge machining was partially flattened by grinding was used as a truer. Diamond grains on the tool working surface were successfully flattened along the hemispherical tool profile when the grains mesh size of #1000 was employed. In addition, a grinding test using glasslike carbon as a work material revealed that a surface roughness of less than 50 nm Rz could be obtained in both cases when moving the tool on contour and scanning paths.

Software Design of Pulse Generator Based on Single-Chip Computer and CPLD

2012 ◽  
Vol 201-202 ◽  
pp. 218-221
Author(s):  
Ji Gao ◽  
Xiao Fang Ma ◽  
Qing Yang Liu
Keyword(s):  
Electrical Discharge ◽  
Pulse Generator ◽  
Low Voltage ◽  
Electrical Discharge Machining ◽  
Pulse Signal ◽  
Pulse Power ◽  
Technical Requirement ◽  
Signal Source ◽  
Single Chip ◽  
Single Chip Computer

The purpose of this article is to study and devise pulse signal source of electrical discharge machining(EDM). The technology of EDM is the necessary key technology in various processing methods. Electrical discharge machining pulse power aims to convert the industrial frequency alternating current into certain frequencies pulse current to supply energy for electrode discharging to removal metal. Pulse power generator, controlled by an embedded MCU, can produce high voltage or low voltage discharge pulse waveform. After the research on characteristics and principles of many pulse powers, a novel, intelligent, high frequency pulse power supply with adjustable amplitude, frequency and duty is developed which has a favorable foreground in engineering application and a great theoretical significance. This paper is to realize the design of EDM pulse signal source based on the method of combining single-chip computer and complex programmable logic devices (CPLD), to satisfy the technical requirement of periodic variable and machining efficiency improving.

Electrical Discharge Machining of Submicron-Diameter Micropins

2010 ◽  
Vol 447-448 ◽  
pp. 238-241 ◽  
Author(s):  
Hiromitsu Ueno ◽  
Yuki Kono ◽  
Kai Egashira
Keyword(s):  
Electrical Discharge ◽  
Tungsten Wire ◽  
Open Circuit Voltage ◽  
Pulse Generator ◽  
Electrical Discharge Machining ◽  
Open Circuit ◽  
Tool Electrode ◽  
Stray Capacitance ◽  
Finish Machining ◽  
The Wire

The wire electrodischarge grinding (WEDG), which is one of the electrical discharge machining (EDM) methods, of submicron-diameter zinc micropins was attempted using a relaxation-type pulse generator. Tungsten wire of 30 µm diameter was employed as the tool electrode. The open-circuit voltage was set at lower than or equal to 15 V in the finish machining step. The electrostatic capacitance of the pulse generator was its stray capacitance only. As a result, a micropin of 0.3 µm diameter was processed. They are the smallest-diameter micropins fabricated by EDM, to the best of our knowledge.

Research on Micro EDM Machine Tool for Machining Micro Array Holes

2012 ◽  
Vol 472-475 ◽  
pp. 2401-2404 ◽  
Author(s):  
Guo Zheng Zhu ◽  
Ji Cheng Bai ◽  
Yong Feng Guo ◽  
Peng Ju Hou ◽  
Chao Jiang Li
Keyword(s):  
Machine Tool ◽  
Electrical Discharge ◽  
Pulse Generator ◽  
Electrical Discharge Machining ◽  
Micro Edm ◽  
Generator System ◽  
Micro Nozzle ◽  
Micro Electrical Discharge Machining ◽  
Micro Array ◽  
New Type

As demands for the micro array holes in modern industry and the characteristics of micro Electrical Discharge Machining (micro EDM), a new type micro EDM machine tool used to machine micro array holes was designed and manufactured. The machine tool contains following systems: the mechanism system, the control system, the pulse generator system and other auxiliary systems. Each system was studied respectively. Base on a large number of experiments, finally, a sample with 256 array holes was processed by the machine tool. The diameter of single hole is 45µm and precision of the holes is ±1µm. The sample has been successfully applied to R & D test of micro nozzle components

Micro Electrical Discharge Machining of Tungsten Carbide with Ultra-Short Pulse

2015 ◽  
Vol 651-653 ◽  
pp. 759-764
Author(s):  
Oliver Kröning ◽  
Mathias Herzig ◽  
Matthias Hackert-Oschätzchen ◽  
Ralf Kühn ◽  
Henning Zeidler ◽  
...  
Keyword(s):  
Electrical Discharge ◽  
Pulse Generator ◽  
Electrical Discharge Machining ◽  
Short Pulse ◽  
High Surface ◽  
Micro Edm ◽  
High Surface Quality ◽  
Micro Electrical Discharge Machining ◽  
Metal Machining ◽  
Ultra Short Pulse

Micro EDM (Electrical Discharge Machining) is a known nonconventional process for the machining of hard to cut materials. Due to its ablating nature based on melting and evaporation through heat induced by electrical discharges, it can function independently of the hardness, toughness or brittleness of the workpiece. Thus micro EDM is a possible process to fulfill the requirements of higher precision and high quality in carbide metal machining. Thereby the surface and the roughness of machined carbide metals depend on the discharge energy used. For machining carbide metals with high surface quality pulse generators with ultra-short discharges are required. This paper presents the development of a two-staged pulse generator with the ability to provide ultra-short pulses by using a two-staged pulse. The current and voltage signals of the discharges were recorded and their characteristics were analyzed.

Performance Improvement of Ultrasonic-Assisted Grinding Using PCD Micropin Tools

2020 ◽  
Author(s):  
Kai Egashira ◽  
Keishi Yamaguchi ◽  
Minoru Ota
Keyword(s):  
Tool Life ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Polycrystalline Diamond ◽  
High Wear Resistance ◽  
Ultrasonic Assisted Grinding ◽  
Ultrasonic Assisted ◽  
Hard And Brittle Materials ◽  
Peripheral Surface ◽  
Drilling Conditions

Abstract In the present study it was attempted to improve the performance of ultrasonic-assisted grinding using polycrystalline diamond (PCD) micropin tools processed by electrical discharge machining. The micropins acted as grinding tools because the convex parts of discharge craters can serve as cutting edges of abrasive grains in grinding wheels. The drilling conditions to prevent chippings and cracks on the hole edge were experimentally determined and then employed for the drilling of microholes less than 10 μm in diameter. As a result, microholes as small as 5.5 μm in diameter were successfully drilled in hard and brittle materials such as crown glass and monocrystalline silicon. The high wear resistance of PCD improved the tool life, making it possible to mill trenches and to mass-produce holes using a small number of tools. Moreover, the tool life was further improved by processing the tool peripheral surface at a low electrical discharge energy.

Sign in / Sign up

Export Citation Format

Share Document