EDM Process Research Articles

Design and manufacturing of waveguide of parabolic antenna using EDM process

Wireless technology was one of the main areas of research in the world of communication system today and a study of communication incomplete without an understanding of the operation and manufacturing of waveguide of parabolic antenna. Waveguide is an important electromagnetic wave transmission Component of parabolic antenna. potential benefits of parabolic antenna doesn’t required any cables to transmitte electromagnetic signal. Designing of waveguide was a most important role before its manufacturing. An attempt is made to design and manufacture the waveguide by varying cross- section using CREO software. Manufacturing of waveguide Carried out by milling, the inner pocket of waveguide was machined by Electrical discharge machining process. Which results accurate surface and suitable for travelling of electromagnetic wave without any disturbance.

Influence of carbon coated WC electrode on drilling measures of Ti–6Al–4V alloy in µ - EDM process

Influence of carbon coated WC electrode on drilling measures of Ti–6Al–4V alloy in µ - EDM process

Experimental Investigation on the Effect of EDM Wire Cut Parameters on the Formation of Cr<sub>23</sub>C<sub>6</sub> in AISI 316 Steel

Wirecut Electrical Discharge Machining (WEDM) is a manufacturing process typically used to manufacture the machinery components in marine application with complex and challenging shapes and profiles. This study aims to investigate the effect of the EDM wire cut parameters on AISI 316 steel by analyzing the formation of Cr23C6. Cr23C6 can be formed in the grain boundary if the stainless steel is sensitized to a high temperature for too long. This compound becomes susceptible to intergranular corrosion than can reduce structural strength. The formation of Cr23C6 is of interest because this compound becomes vulnerable to intergranular corrosion than can reduce structural strength. The experimental variables in this study are pulse on time (i.e., 8 μs and 12 μs), servo voltage (i.e., 20 V and 30 V), and wire feed (i.e., 5 mm/min and 9 mm/min). The 0.2 mm brass wire is used during the EDM process. The result is then analyzed by surface roughness test, scanning electron microscope (SEM), and Energy-dispersive X-ray spectroscopy (EDS). As a result, the highest and lowest surface roughness values are 2.526 μm 1.771 μm, respectively. SEM results are seen in the pores of holes (craters) and fractures (microcracks). The result of EDS is the additions of elements Carbon (C) and copper (Cu), Oxygen (O). Increased carbon Chrom in HAZ sections allows for corrosion of grain limits.

Microtexturing D2 steel surface to induce superhydrophobicity on it using EDM process

Microtexturing D2 steel surface to induce superhydrophobicity on it using EDM process

Study the effect of EDM parameters on surface roughness of cryogenically treated AISI 304 steel

Powder mixed electric discharge machining (PMEDM) has an edge over the conventional EDM process owing to the presence of electrically conductive powder nixed in the dielectric fluid to achieve improved surface integrity of machined components. Cryogenic treatment of work material and tool material has the potential to yield better machining performance in the EDM process. This paper presents the findings of the experimental investigation subjected to the application of PMEDM to machine cryogenically treated AISI 304 using the cryogenically treated electrode made of Copper. The RSM-based approach was deployed to design the experiments to study the influence of parameters viz. powder concentration, current, pulse-on time, and duty cycle on surface roughness. A regression analysis was carried out to establish a relationship between surface roughness and given machining parameters which were also validated through residual plots.

Optimization of EDM process parameters using MCDM based on customer preference rating method

Nowadays, multi-objective optimization tools have been used in manufacturing processes to decide the optimal process parameters. Optimization method with a more advanced tool is required to obtain the finest EDM process parameters such as peak current, voltage, pulse on duration, pulse off duration, pressure. This research work utilizes the Multi-Criteria Decision Making Method (MCDM) for identifying the optimal process parameters according to customer preference rating method (CPR). CPR draws a weightage to the output responses of the machine and characteristics of the machined surface as per customer requirement. Genetic Algorithm (GA) and TOPSIS are extensively involved in solving multi-objective optimization problems. Optimization of process parameters were determined using Genetic Algorithm (GA) integrated with TOPSIS to achieve higher Metal Removal Rate, Micro Hardness, low surface roughness, tool wear rate and actual depth. There are fifty Pareto-optimal solutions performed and the best solution has been selected based on rank. The optimal solution of the GA was given to the TOPSIS as input for further improvement. The optimal value obtained through GA has been enhanced with TOPSIS.

High-efficiency EDM based on a composite pulse current

EDM technology is still facing a big bottleneck problem unsolved: low molten material removal rate, resulting in low machining speed and poor surface quality. To improve the material removal amount in each discharge process of EDM, the composite pulse current waveforms were proposed. The single pulse discharge experiments demonstrate that under the same discharge energy, the material removal volume in the discharge with the end composite pulse could be twice as high as that with the square pulse. Furthermore, due to high molten material removal rate of the end composite pulse, the thickness of the recast layer generated in the discharge with the end composite pulse was much thinner than that with the square pulse under the same discharge energy. The MD simulation results also revealed that in the discharge with the end composite pulse, the basic current mainly melted the material to form a larger molten pool, then, the inrush current, which had higher energy density and higher material removal motivity, could remove the molten pool material largely. Thus, the end composite pulse can improve the molten material removal rate and decrease the recast layer. Finally, EDM milling experiments show that higher average material removal volume in each discharge process of EDM milling with the end composite pulse was the main reason for higher material removal rate (MRR) in EDM milling with the end composite pulse. In addition, the relative tool wear ratio (RTWR) in EDM milling with the end composite pulse can be approximately equal to or slightly lower than that with the square pulse at a high material removal rate in EDM milling, which shows a great application potential of the end composite pulse in EDM.

Investigation on tool wear mechanisms and machining tribology of hardened DC53 steel through modified CBN tooling geometry in hard turning

DC 53 steel has emerged as a possible replacement of AISI D2 steel possessing competitive hardness and better toughness. In the current work, turning of DC 53 steel was conducted via Xcel modified inserts by varying workpiece hardness levels (40 and 60 HRC), cutting speed (130 and 160 m/min), feed rate (0.07 and 0.112 mm/rev), and depth of cut (0.07 and 0.17 mm). A two-level 4-factor full factorial design was employed entailing 16 runs. An analysis of variance (ANOVA) was conducted to statistically analyze the effect and contributions of input parameters on response variables namely tool life, surface roughness, volume of material removed, power consumption, and machining zone temperature. Results show that the tool life, surface roughness, volume of material removed, and machining zone temperature are primarily affected by the hardness of DC53 with PCRs of ~ 96%, ~ 25%, ~ 62%, and ~ 25%, respectively. At a 40 HRC hardness value, true crater wear was observed due to continuous chips sliding at the rake face while for the workpiece having a 60 HRC, discontinuous chip formation produced less prominent crater wear. SEM images revealed complete delamination of the coating from the tool surface with adhesion and attrition wear identified as the main wear mechanisms. The formation of a groove pattern was also noticed on the flank face. The minimum surface roughness was 0.90 µm-Ra for the workpiece having a 40 HRC hardness level, and the same value was obtained for 60 HRC as well. The threshold value of the feed rate for the excellent performance of these inserts was less than 0.20 mm/rev. Additionally, the turning process proved to be productive for this material along with a lower surface roughness value in comparison to the wire EDM process.

A review on parametric optimization of EDM process for nanocomposites machining: experimental and modelling approach

A review on parametric optimization of EDM process for nanocomposites machining: experimental and modelling approach

Study of discharge characteristics and multi objective optimisation of machining parameters in ultrasonic vibration assisted micro electrical discharge machining

Micro-EDM is a non-traditional manufacturing technique that uses the heat energy of the plasma to remove material. When there is a sufficient electric potential between two electrodes, the dielectric in between becomes ionised, resulting in the formation of a plasma channel. The net discharge energy produced is the result of the current and voltage present at the inter-electrode gap (IEG). The current and voltage waveforms obtained from the oscilloscope are used to calculate the discharge energy. A small part of this discharge energy gets converted as plasma temperature, which facilitates material removal in micro-EDM. Because plasma is the only source of heat, its properties must be studied. In the present study, Optical Emission Spectroscopy is used to calculate the temperature of the plasma. This article explores the scope of a hybrid micro EDM process, where an ultrasonic vibration is integrated to the tool electrode. A systematic approach using Response Surface Methodology is employed for modelling and analysis of plasma properties and material removal in micro EDM. Two types of input parameters were chosen: Voltage and pulse on time being the electrical parameters, and Amplitude and Frequency as the vibrational parameters. Dielectric used is deionised water. A single spark experiment was performed on Nitinol Shape Memory Alloy and tool used was of same material. Ultrasonic vibration was provided to the tool using a piezoelectric actuator. It was found that electrical parameters have a significant impact in determining plasma properties and material removal properties. Vibrational parameters play a vital impact in enhancing the crater’s surface features.

FEM modeling for predicting temperature profile of heat affected zone in single spark EDM process

FEM modeling for predicting temperature profile of heat affected zone in single spark EDM process

Efficiency of the Machining Process of Circular Shapes by Electrical Discharge Technology

Due to its high machining precision, EDM technology is nowadays very important in the production of high-precision parts for various industries. The high precision of the machined surface in combination with the ability to machine circular surfaces brings, in addition to several advantages, some negatives. The most significant negative of this machining technology is the relatively low productivity as well as the overall production efficiency. The latter is affected by many accompanying phenomena. The main accompanying phenomenon that contributes to the decline in the overall economic efficiency of EDM is the microgeometry errors that occur due to the non-homogeneity of the EDM process. Another accompanying negative phenomenon is the geometric accuracy errors of the machined surface, as a consequence of systematic destruction of the wire tool electrode, faulty interpolation in its guidance, and, last but not least, its vibration. These aspects consequently lead to the requirement for multiple applications of additional finishing cuts, which significantly reduces the overall economic efficiency of the machining process. Therefore, the experimental research aimed to search for options that can effectively help to achieve higher productivity but especially the overall economic efficiency of the machining process.

Multimethod analysis of three rotary instruments produced by electric discharge machining technology.

This study aimed to compare three rotary instruments produced by the EDM process with the heat-treated ProTaper Gold system regarding design, metallurgy, mechanical properties and shaping ability. HyFlex EDM (25/~), Neoniti (25/.06), EDMax (25/.06) and ProTaper Gold (25/.08v) instruments (n = 58 per group) were compared regarding design, metallurgy and mechanical performance. Unprepared canal areas were calculated for each system after preparation of mesiobuccal, mesiolingual and distal canals of mandibular molars (15 canals per group) using micro-CT technology. Statistical analyses were performed using One-way anova post-hoc Tukey and Kruskal-Wallis post-hoc Dunn's tests (α = 5%). All instruments had asymmetrical blades, no radial lands, no major defects and almost equiatomic nickel/titanium ratios, but different cross-section designs, tip geometries and surface appearances. Although instruments had distinct transformation temperature curves, they showed crystallographic martensitic arrangement at 21°C and mixed austenite plus R-phase at body temperature. Neoniti and HyFlex EDM showed similar results in all mechanical tests (p > .05), while EDMax and ProTaper Gold had similar time to fracture (p = .841), maximum bending load (p = .729), and cutting ability (p = .985). ProTaper Gold showed the highest torque to failure (p < .001) and HyFlex EDM had the lowest buckling resistance (p < .001). Mean percentages of unprepared canal areas ranged from 20.4% to 25.7% in the mesial canals, and from 20.8% to 26.2% in the distal canal, with no statistical differences among systems (p > .05). Instruments' geometry and phase transformation temperatures influenced the results of the mechanical tests, but not their shaping ability.

Multi-response optimization of machining parameters of Ti-6Al-2Sn-4Zr-2Mo alloy using EDM process through grey relational analysis

Due to its high corrosion resistance and low density, it is tedious to machine high strength materials such as titanium alloy for the manufacture of engineering products related to aerospace, automobiles, and medical applications. In this study, an attempt was made to consider the impact of tool electrodes in the electrical discharge machining method for successful machinability of titanium alloy. High temperatures are used during electrical discharge machining to melt and vaporise the hard titanium alloy. In the current work, an EDM machining method was used to machine a Ti-6Al-2Sn-4Zr-2Mo alloy while using the input parameters of pulse on time, voltage, and current as process parameters. The experiments were carried out based on the workpiece, and surface morphology was performed on the workpiece surface. The process parameters were optimised using the Multi-Response Grey Relation Analysis method, and a major effects plot was created to see how the factors affected the MRR and surface roughness. Surface finish and MRR have been discovered to be directly correlated with discharge current. These are the best process parameters for machining pulse on time (150 s), voltage (60 V), and discharge current (16 A).

A review of modeling and simulation techniques in EDM process

This paper presents a review of modeling and simulation techniques presented in the literature for Electrical Discharge Machining process parameter optimization and prediction. The techniques covered include statistical prediction models, Machine Learning (ML)-based prediction models, theoretical models, experimental models and thermal-electrical models using FEM developed by researchers. A brief description of the literature including work material, technique, software and their findings are also tabulated to get a quick insight of the work done by the researchers. The salient features of the various techniques are also highlighted for guiding the future research in this area.

Micro ECDM scanning process with feedback control of flexible contact force

Quartz glass has been widely used in frontier fields of MEMS (micro electro-mechanical systems) and sensors due to its excellent chemical and mechanical properties. Although ECDM (electrochemical discharge machining) is a non-traditional material removal process suitable for machining electrically non-conductive materials of high temperature resistance and hard brittleness, the adopted feeding strategy of tool electrode directly affects the machining results, especially in a micro ECDM scanning process. The existing feed methods still cannot maintain a suitable machining gap with a minimum given contact force during the micro ECDM scanning process, causing inconsistent gap state and the damage to machining stability and geometric accuracy of micro structures. In this research, a novel spindle combining a flexure hinge and a high-resolution micro-force sensor is designed, achieving the function of real-time servo control of a given micro contact force. Using the micro tool electrodes (<Φ200 μm) fabricated by the combined process of reverse-copying micro EDM and TF-WEDG (tangential feed-wire electrode discharge grinding), the circular structures are successfully machined on quartz glass with the optimized parameters of open-circuit voltage, scanning speed, and number of scanning. To guarantee the consistent depth along a scanning layer, a feed strategy of quantified depth with servo control of flexible micro force (SCFMF-QDFS) is proposed, and micro 3D structures of S-shape and square are machined with controllable accuracy of ±2 μm and ±4 μm in depth and width.

Одноступенчатое технологическое обеспечение износостойкости деталей машин электроэрозионной обработкой

Theoretical dependences for deter-mining the wear intensity, depending on the modes and conditions of EDM process of ma-chine parts based on the energy approach to the processing and triboprocess, are given. These dependences make it possible to determine the optimal modes and conditions of EDM process for ensuring the required parameters of wear resistance (with a single-stage approach – di-rect engineering support).

Influence of the surface finishing on the wear behaviour of cemented carbides worked by Electrical Discharge Machining

Cermets are materials, usually made of hard ceramic particles embedded in metal matrix, widely used in different technological fields typically produced by powder metallurgy processes. The combination of the two materials results in a material with superior properties respect to either material alone. One of the most used technology to obtain the final shape of the cermets is the Electrical Discharge Machining process (EDM), which involve some microstructural alterations that influence the tribological behaviour. In this work, several cermet samples were processed using the EDM process. The samples were then subjected to different surface finishing processes such as sandblasting, grinding, lapping and their combinations to reduce the effect of the EDM altered surface layer.The near surface of the samples was analysed in terms of: microstructure (SEM + EDX), surface texture (stylus profilometer), chemical composition (RF-GDOES). A detailed tribological characterization was performed in ball-on-flat configuration at several different loads (20 N, 40 N, 80 N) in order to simulate similar conditions of cold rolling rolls. The worn samples were then characterized in order to measure the wear rate and identify the wear mechanisms.The obtained results showed that the EDM process leaves an altered layer that alters the surface of the samples and influences the wear performance of the sample. The removal of this layer completely change the tribological material response in terms of wear rate and coefficient of friction.

On application of tool mimic approach for fabrication of functional surfaces using EDM process

On application of tool mimic approach for fabrication of functional surfaces using EDM process

Behavior and damage of the near-surface layer of parts pre-machined by the EDM process

Behavior and damage of the near-surface layer of parts pre-machined by the EDM process