Microstructure and Electrode Discharge Machining of TiN/Si3N4 Composites

2005 ◽  
Vol 475-479 ◽  
pp. 1337-1340
Author(s):  
Chien Cheng Liu ◽  
Jow Lay Huang
Keyword(s):  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Ceramic Composites ◽  
Tool Electrode ◽  
Electrode Wear ◽  
Micro Edm ◽  
Si3n4 Ceramic ◽  
Whole Process ◽  
Electrode Discharge ◽  
Scanning Electron

Conductive TiN/Si3N4 ceramic composites were processed by electrical discharge machining (EDM) and their microstructure and conductivity investigated. A low electrical resistivity of 1.25×10-3Ω.cm was obtained in 40vol%TiN/Si3N4 composite. The whole process of tool electrode wear is evaluated by sinker-EDM. The machined surfaces of TiN/Si3N4 ceramic composites were examined by scanning electron microscopy (SEM) and profilometry to determine the surface finish. Micropores of 700µm in depth and 70µm in diameter were successfully machined in TiN/ Si3N4 composites by the micro-EDM method.

Recent Patents on Micro-EDM Milling

2020 ◽  
Vol 13 (3) ◽  
pp. 219-229
Author(s):  
Baocheng Xie ◽  
Jianguo Liu ◽  
Yongqiu Chen
Keyword(s):  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Three Dimensional ◽  
Processing Method ◽  
Electrode Wear ◽  
Micro Edm ◽  
Processing Efficiency ◽  
Processing Methods ◽  
Machining Quality ◽  
Micro Electrical Discharge Machining

Background: Micro-Electrical Discharge Machining (EDM) milling is widely used in the processing of complex cavities and micro-three-dimensional structures, which is a more effective processing method for micro-precision parts. Thus, more attention has been paid on the micro-EDM milling. Objective : To meet the increasing requirement of machining quality and machining efficiency of micro- EDM milling, the processing devices and processing methods of micro-EDM milling are being improved continuously. Methods: This paper reviews various current representative patents related to the processing devices and processing methods of micro-EDM milling. Results: Through summarizing a large number of patents about processing devices and processing methods of micro-EDM milling, the main problems of current development, such as the strategy of electrode wear compensation and the development trends of processing devices and processing methods of micro-EDM milling are discussed. Conclusion: The optimization of processing devices and processing methods of micro-EDM milling are conducive to solving the problems of processing efficiency and quality. More relevant patents will be invented in the future.

scholarly journals An Influence of Parameters of Micro-electrical Discharge Machining on Wear of Tool Electrode

2017 ◽  
Vol 64 (2) ◽  
pp. 149-163 ◽  
Author(s):  
Govindan Puthumana
Keyword(s):  
Tool Wear ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Tool Electrode ◽  
Micro Edm ◽  
Modeling And Analysis ◽  
Micro Electrical Discharge Machining ◽  
Wear Ratio ◽  
Tool Wear Ratio ◽  
Main Effect

AbstractTo achieve better precision of features generated using the micro-electrical discharge machining (micro-EDM), there is a necessity to minimize the wear of the tool electrode, because a change in the dimensions of the electrode is reflected directly or indirectly on the feature. This paper presents a novel modeling and analysis approach of the tool wear in micro-EDM using a systematic statistical method exemplifying the influences of capacitance, feed rate and voltage on the tool wear ratio. The association between tool wear ratio and the input factors is comprehended by using main effect plots, interaction effects and regression analysis. A maximum variation of four-fold in the tool wear ratio have been observed which indicated that the tool wear ratio varies significantly over the trials. As the capacitance increases from 1 to 10 nF, the increase in tool wear ratio is by 33%. An increase in voltage as well as capacitance would lead to an increase in the number of charged particles, the number of collisions among them, which further enhances the transfer of the proportion of heat energy to the tool surface. Furthermore, to model the tool wear phenomenon, a regression relationship between tool wear ratio and the process inputs has been developed.

Research of the Basic Physical Regularities of Material Removal in Electrical Discharge Machining of Tool Steel

2017 ◽  
Vol 756 ◽  
pp. 96-106
Author(s):  
Ľuboslav Straka ◽  
Slavomíra Hašová
Keyword(s):  
Tool Steel ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Main Process ◽  
Tool Electrode ◽  
Electrode Wear ◽  
Workpiece Material ◽  
The Individual ◽  
Selection Of

The paper describes the basic physical regularities of material removal in Electrical discharge machining (EDM) of tool steel. One of the parameters, that material removal regularities quite accurately identifies, is the tool wear rate (TWR). This parameter, however, describes only the regularities concerning the tool electrode wear. More complex parameter for assessing regularities of material removal in EDM is thus electrode wear ratio (EWR). This parameter, except the size of the wear of the tool electrode, also describes the size of the workpiece material removal. Research on material removal was carried out on samples made out of tool steel EN X32CrMoV12-28 using Cu-ETP electrode EN CW004A. Aim of this paper was also based on the selection of main process parameters that significantly influence the material removal in EDM to define the individual specifics with regard to minimizing EWR.

scholarly journals Technical Model of Micro Electrical Discharge Machining (EDM) Milling Suitable for Bottom Grooved Micromixer Design Optimization

Micromachines ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 594 ◽  
Author(s):  
Izidor Sabotin ◽  
Gianluca Tristo ◽  
Joško Valentinčič
Keyword(s):  
Design Optimization ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Electrode Wear ◽  
Micro Edm ◽  
Efficient Design ◽  
Machining Time ◽  
Micro Electrical Discharge Machining ◽  
Technical Model

In this paper, development of a technical model of micro Electrical Discharge Machining in milling configuration (EDM milling) is presented. The input to the model is a parametrically presented feature geometry and the output is a feature machining time. To model key factors influencing feature machining time, an experimental campaign by machining various microgrooves into corrosive resistant steel was executed. The following parameters were investigated: electrode dressing time, material removal rate, electrode wear, electrode wear control time and machining strategy. The technology data and knowledge base were constructed using data obtained experimentally. The model is applicable for groove-like features, commonly applied in bottom grooved micromixers (BGMs), with widths from 40 to 120 µm and depths up to 100 µm. The optimization of a BGM geometry is presented as a case study of the model usage. The mixing performances of various micromixer designs, compliant with micro EDM milling technology, were evaluated using computational fluid dynamics modelling. The results show that slanted groove micromixer is a favourable design to be implemented when micro EDM milling technology is applied. The presented technical model provides an efficient design optimization tool and, thus, aims to be used by a microfluidic design engineer.

Study on electrical discharge machining for cemented carbide with non-flammable dielectric liquid: Influence of form of oxygen supplied to dielectric liquid on machining

2017 ◽  
Vol 232 (4) ◽  
pp. 568-577 ◽  
Author(s):  
Masahiro Yoshida ◽  
Yuu Ishii ◽  
Takemi Ueda
Keyword(s):  
Hydrogen Peroxide ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Dielectric Liquid ◽  
Cemented Carbide ◽  
Tool Electrode ◽  
Electrode Wear ◽  
Machining Speed ◽  
Machining Characteristics ◽  
Oil Type

One of the problems faced in the finish electrical discharge machining of cemented carbide is the slow machining speed due to frequent abnormal discharges and concentrated discharge. To resolve this problem, in this study, attempts were made to supply oxygen to oil-type non-flammable dielectric liquid used in finish electrical discharge machining. First, the effects of the form of the oxygen when it is supplied to the dielectric liquid were investigated. As a result, it was found that when oxygen is supplied to the machining gap in the microbubble state, machining is not affected at all. When dissolved in the dielectric liquid and supplied, machining speed was seen to improve. Next, machining experiments were conducted, varying the percentage of 35 wt% hydrogen peroxide water mixed with the dielectric liquid to change the amount of oxygen in the dielectric liquid. As a result, the following were clarified. (1) The machining speed was six times faster than normal dielectric liquid when 15 wt% of oxygen was mixed; (2) at this time, the tool electrode wear had decreased to one-fifth that of normal dielectric liquid; (3) the surface roughness obtained was below Ra 1 µm regardless of the mixed percentage of hydrogen peroxide water; and (4) better machining characteristics were obtained when the workpiece was set as the positive electrode.

An Experimental Study of the Phenomenon of Surface Alloying by EDM Process Using Inconel Tool Electrode

2013 ◽  
Author(s):  
Sanjeev Kumar
Keyword(s):  
Experimental Study ◽  
Surface Properties ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Plasma Channel ◽  
Machining Process ◽  
Tool Electrode ◽  
Electrode Wear ◽  
Surface Alloying ◽  
Machining Conditions

Electrical Discharge Machining (EDM) has emerged as a very important machining process due to its numerous advantages. It is extensively used by the die and toolmaking industry for the accurate machining of complex internal profiles. Although EDM is essentially a material removal process, it has been used successfully for improving the surface properties of the work materials after machining. As the dissolution of the electrode takes place during the process, some of its constituents may alloy with the machined surface under appropriate machining conditions. Additive powders in the dielectric medium may form part of the plasma channel in the molten state and produce similar alloying effect. The breakdown of the hydrocarbon dielectric under intense heat of the spark contributes carbon to the plasma channel. Sudden heating and quenching in the spark region also alters the surface properties. This paper reports the results of an experimental study into electrical discharge machining of H13 hot die steel with Inconel (an alloy of chromium, nickel and iron) tool electrode under machining conditions favouring high electrode wear. The results show improvement in micro-hardness after machining by as much as 88%. Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) analysis of the machined surfaces show transfer of chromium and nickel from the tool electrode. Both these elements form intermetallic compounds as well as solid solution with iron and strengthen it. It was found that percentage of chromium increased from 5.39% to 6.52% and that of nickel increased from 0.19% to 4.87%. The favourable machining conditions for surface alloying were found to be low value of peak current, shorter pulse on-time, longer pulse off-time and negative polarity of the tool electrode.

Experimental Research on Technology of Ultrasonic Vibration Aided Electrical Discharge Machining (UEDM) in Gas

2006 ◽  
Vol 315-316 ◽  
pp. 81-84 ◽  
Author(s):  
Qin He Zhang ◽  
Jian Hua Zhang ◽  
Q.B. Zhang ◽  
Shu Peng Su
Keyword(s):  
Ultrasonic Vibration ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Tool Electrode ◽  
Electrode Wear ◽  
Machining Parameters ◽  
Environment Pollution ◽  
Dielectric Fluids

Ultrasonic vibration aided electrical discharge machining (UEDM) in gas is an electrical discharge machining (EDM) technology, in which gases such as air and oxygen are used as dielectrics and ultrasonic vibration is applied. UEDM in gas can avoid environment pollution, the most serious disadvantage of conventional EDM in kerosene-based oil or other dielectric fluids, and it is environmental-friendly. The technology also possesses virtues of wide applications, high machining efficiency and simple tool electrodes and so on. The principle of UEDM in gas is introduced in this paper. Experiments have been carried out to study the effects of machining parameters on material removal rate (MRR), surface roughness of the workpiece and tool electrode wear ratio (TWR), and the experiments results have also been analyzed.

A Simulation Study on Rod Electrode Wear in Micro-EDM

2012 ◽  
Vol 472-475 ◽  
pp. 2426-2429 ◽  
Author(s):  
Hu Wang ◽  
Yuan Gang Wang ◽  
Meng Hua Wu ◽  
Xiao Peng Li ◽  
Yu Liu
Keyword(s):  
Adverse Effect ◽  
Finite Element Analysis ◽  
Finite Element ◽  
Electrical Discharge ◽  
Skin Effect ◽  
Electrical Discharge Machining ◽  
Electrode Wear ◽  
Micro Edm ◽  
Element Analysis ◽  
Micro Electrical Discharge Machining

Electrode wear has a great adverse effect on the accuracy of Micro Electrical Discharge Machining (Micro-EDM) and impedes the improvement of Micro-EDM. In this study the distribution of electric field and current density was analyzed exhaustively in order to explore the generating mechanisms of rod electrode wear by finite element analysis and experiment. Experimental results indicated that corner wear occurred first, followed by side wear resulted from skin effect and debris in Micro-EDM, which was significant in enhancing the accuracy of machining.

The Deposition and Removal Process for Micro Machining Based on Electrical Discharge

2012 ◽  
Vol 472-475 ◽  
pp. 2448-2451
Author(s):  
Zi Long Peng ◽  
Yi Nan Li
Keyword(s):  
Electrical Discharge ◽  
Deposition Process ◽  
Process Conditions ◽  
Tool Electrode ◽  
Electrode Wear ◽  
Discharge Process ◽  
Micro Edm ◽  
Micro Machining ◽  
Removal Process ◽  
Micro Structures

Based on the analysis of electrical discharge process characteristics, the principle of achieving deposition process and removal process using micro EDM is proposed. By controlling the tool electrode wear in one micro EDM system, it is easy to achieve the different machining type of deposition or removal process. Centering on the problem of tool electrode wear, the process conditions of the deposition and removal including machining polarity, machining dielectric medium, discharge parameters and the tool electrode rotation are researched detailedly. Results show that under the discharge phenomena between electrodes, metal material can be deposited to form micro structures, and the transfer strategy from deposition to removal process can be controlled easily. The machining procedure for fabrication of micro structures based on depostion and removal process are put forward. And finally, some examles with well shape and dimension accuracy are given to validate the processing ability for micro machining.

Sign in / Sign up

Export Citation Format

Share Document