Electro-discharge Machining Performance Research Articles

Predictive modeling of MRR, TWR, and SR in spark-EDM of Al-4.5Cu–SiC using ANN and GEP

In this study, Al-4.5Cu alloy was reinforced with varying weight percentages of SiC particles (2%, 4%, 6%, and 8%) to create metal matrix composites via the stir casting method. The formation of intermetallic compounds was confirmed through energy dispersive spectroscopy and x-ray diffraction analysis. This article compares the performance of Artificial Neural Network (ANN) and Gene Expression Programming (GEP) models in predicting the Metal Removal Rate (MRR), tool wear rate, and surface roughness in the die-sinking electro-discharge machining (EDM) process of the ex-situ developed Al-4.5%Cu–SiC composites. The study considers three machine parameters—pulse on time (TON), pulse off time (TOFF), and current (I)—along with the weight fraction of SiC particles as input variables for the models. Both ANN and GEP models demonstrated high predictive accuracy for the EDM performance metrics, with correlation coefficients (R) ranging from 0.973 68 to 0.980 65 for the ANN model and 0.980 11 to 0.982 59 for the GEP model. Notably, the GEP model exhibited superior predictive capability, as evidenced by its higher correlation coefficients and lower root mean square error, indicating greater effectiveness in predicting the EDM process outcomes than the ANN model.

Parametric Investigation of Die-Sinking EDM of Ti6Al4V Using the Hybrid Taguchi-RAMS-RATMI Method

Ti6Al4V is a widely used alloy due to its excellent mechanical qualities and resistance to corrosion, which make it fit for automotive, aerospace, defense, and biomedical sectors. Due to its high strength and limited heat conductivity, it is difficult to machine. Both the workpiece’s and the electrode’s conductivity are important factors that impact the electro-discharge machining (EDM) process. In this case, the machining efficiency is also influenced by the electrode selection. As a result, choosing the right electrode and machining parameters is essential to improving EDM performance on the Ti6Al4V alloy. Research on EDM for Ti6Al4V is limited, with little focus on electrode material selection and shape. The impact of EDM settings on MRR, TWR, and surface roughness is complex, and a comprehensive optimization strategy is needed. Copper electrodes are widely used, but further investigation is needed on EDM’s effects on Ti6Al4V’s surface properties and surface integrity. Addressing these research gaps will improve the understanding and application of EDM for Ti6Al4V, focusing on parameter optimization, surface integrity, and thermal and mechanical effects. By employing copper tools to optimize four crucial EDM process parameters—peak current, duty cycle, discharge current, and pulse-on time—this research aims to increase surface integrity and machining performance. A comprehensive Taguchi experimental design is used to systematically alter the EDM settings. By optimizing parameters using tolerance intervals and response modelling, the recently developed RAMS-RATMI approach improves the dependability of the EDM process and increases machining efficiency. With the optimized EDM settings, there were notable gains in depth of cut enhancement, surface roughness minimization, tool wear rate (TWR) reduction, and material removal rate (MRR). The results of the surface integrity examination showed fewer heat-affected zones, fewer microcracks, and a thinner recast layer. Analysis of variance was used to verify the impact and resilience of the optimized parameters. Superior machining performance, higher surface quality, and increased operational dependability were attained with the Ti6Al4V-optimized EDM process, providing industry practitioners with insightful information and useful recommendations.

Electro discharge machining performance of cryogenic heat treated copper electrode

Abstract In this study, the EDM machining performance of a cryogenic heat treated copper electrode was investigated. Within the scope of the study, electrodes selected from copper material were subjected to cryogenic heat treatment with a cycle between [room temperature/ − 184 °C/room temperature]. In the experimental design, the electrode material was changed at two levels: copper electrode (Cu) and cryogenic copper electrode (CCu). Controllable machine parameters, peak current (Ip), active pulse duration (Ton), pulse gap duration (Toff) and gap voltage (Vg) were changed at three levels. The effects of these parameters on outputs such as recast layer thickness (RLT), material removal rate (MRR), electrode wear rate (EWR) and taper angle (TA), which are taken into consideration in determining the processing quality after EDM machining experiments, were taken into account. A total of 18 experiments were carried out on Ti–6Al–4V (Titanium alloy) workpiece with copper electrode. Lower YKTK with combinations of EDM process parameters such as cryogenic copper electrode (CCu), 4 A peak current (Ip), 110 µs active pulse duration (Ton), 72 µs pulse gap time (Toff) and 6 V gap voltage (Vg), It was observed that EWR and TA and higher MRR were obtained.

Enhancing surface integrity and performance of EDM with sustainable dielectrics and electrode modifications

A common non-traditional method for precise machining of hard materials is electro-discharge machining (EDM). The efficiency and surface quality in the EDM process are decided by the design and type of the electrodes. Because of its lightweight, cost-effectiveness and easy machinability, aluminium is employed in a wide range of applications. In this work, AlSi10Mg electrodes are manufactured by different processing routes such as 3D printing, casting, and extrusion. Different characterization techniques are carried out to determine the mechanical, electrical, and thermal properties of all differently processed aluminium alloy electrodes. The processing route influence during the EDM of Ti-6Al-4V is evaluated with different levels of operating parameters using conventional EDM oil and lemon peel biodiesel as dielectrics. The experiments are performed with 3 different levels of current (Ip) and pulse on time (Ton) with a constant voltage. The output responses viz. material removal rate (MRR), Tool wear rate (TWR), average surface roughness (Ra) and white layer thickness (WLT) are considered to compare the EDM performance exhibited by differently processed aluminium alloy electrodes. The 3D printed aluminium alloy electrode produces about 23% less TWR and 18% improved surface quality than the conventional (extruded) electrode. The performance exhibited by the cast aluminium alloy electrode is sub-optimal when compared to electrodes processed by the other two routes. The microscopic examination revealed that WLT could be reduced to the extent of about 29% and 39% with 3D printed AlSi10Mg electrodes when compared with extruded and cast electrodes. The present study concluded that a 3D printed electrode with lemon peel dielectric is the most preferable combination for high surface finish operation.

Parametric optimizing of electro-discharge machining for LM25Al/VC composite material machining using deterministic and stochastic methods

AbstractThe electro-discharge machining (EDM) process is investigated using deterministic and stochastic methods to determine and model the effects of process parameters on machining performance. The workpiece utilized for the investigation was an LM25 aluminum alloy reinforced with vanadium carbide (VC), processed through a stir casting technique. EDM process parameters like peak current, discharge voltage, and pulse on-time are considered to analyze material removal rate, electrode wearing rate, and surface roughness. This study applied four multi-criteria decision-making (MCDM) and analytical methodologies to evaluate EDM performance. Then, the MCDM scores were compared using two objective verification mechanisms. In this case, the teaching-learning-based optimization (TLBO) technique delivered the best-desired results relative to the VIKOR, Grey relational grade (GRG), and the response surface method (RSM). Also, the RSM and analytical methods are simpler than the other methods, though they produced nearly identical results as the sophisticated MDCM and deterministic methods.

Effect of cryotreated post tempered electrodes on EDM performance of AISI 304

In the present investigation, a comparison study has been conducted to investigate the effect of process parameters and three different type of electrodes {untreated (UT), cryotreated single tempered (CT1) and cryotreated double tempered (CT2)} during electro discharge machining (EDM) operation. For this purpose, WC and AISI 304 stainless steel was used as electrode and work material. Peak current, pulse on time, duty cycle, gap voltage, and flushing pressure were considered as process parameters and performance characteristics were measured by means of tool wear rate (TWR), material removal rate (MRR) and surface roughness (Ra). Microstructural analysis was conducted on the EDMed surfaces machined by UT, CT1 and CT2 electrodes. It is found from the investigation that UT electrode provides higher tool wear rate (TWR), material removal rate (MRR), and surface roughness (Ra) compare to cryotreated post tempered electrodes. Better surface quality has been achieved for EDMed surface machined by CT2 electrode compare to UT and CT1 electrodes.

Utilizing multiple criteria decision-making optimization methods to machine LM25Al/VC material under electro-discharge machining processes

In this work, sparking electro-discharge machining (EDM) process parameters are optimized by using multiple criteria decision-making (MCDM) methods. The work piece utilized for the investigation was LM25 aluminum alloy reinforced with Vanadium carbide (VC), processed through a stir casting technique. The EDM process parameters that have been considered in this work are by peak current, pulse-on-time, and pulse-off-time, with the effects of each variable and their combinations on the performance metrics of EDM like material removal rate, electrode wearing rate, and surface roughness. In this study, three MCDM methodologies were applied to evaluate EDM performance. Then, the obtained MCDM scores were compared using two different objective verification mechanisms. In this case, the VIKOR technique delivered the best-desired results relative to TOPSIS method, and factorial analyzing method. Also, the factorial method is simpler than the other methods, though it produced nearly identical results as the sophisticated MDCM method.

Bio-dielectrics to improve the performance of electro discharge machining – an investigation for cleaner production opportunities

ABSTRACT To tackle the challenges of environmentally friendly dielectric fluid, the current research focuses on the diverse biodegradable oils that are utilised as dielectric fluids in electro-discharge machining (EDM) processes. When it comes to machining extremely hard materials, EDM is a cutting-edge, non-traditional technology. As part of this research, Ti-6Al-4 V material has been machined in two phases: the first phase, using conventional EDM oil, and the second phase, utilising four distinct bio-dielectric fluids. Comparisons have been made between EDM oil and other bio-dielectric fluids in terms of machining performance measures such as material removal rates (MRR), tool wear rate (TWR), and surface roughness (SR). The primary goal of this research is to identify an appropriate bio-dielectric fluid that will be environmentally acceptable, cost-effective, and provide better machining performance when compared to other dielectric fluids on the market. When the MRR, TWR, and SR are taken into account, mixed vegetable oil is found to be the best bio-dielectric fluid, and in cases where only the MRR is considered, sunflower oil is the best dielectric. It was discovered that the surface obtained with sunflower oil is the best in terms of crack size and number of cracks when compared to other dielectric fluids.

Performance of Powder mixed Drilling EDM on Biomedical Ti-6Al-4V Alloy

Titanium alloys have gained a lot of attention in biomedical due to their novel properties. In fact, their low elastic modulus and good biocompatibility have promising potential in load bearing bone replacement implants. However, a big part of successful implantation relies on proper surface treatment, which can enhance its performance. Electro discharge machining (EDM) is one of the surface treatment techniques that can be beneficial for proper surface forming. For that reason, this study investigates the machining conditions of EDM on Ti-6Al-4V titanium alloy. In details, this paper evaluates the effect of machining parameters of pulse current, time-on, time-off, gap voltage and powder on material removal rate (MRR) and overcut. Moreover, an experiment set based on L9(34) Taguchi’s orthogonal array was conducted and the analysis of variance was observed. In order to investigate the optimum machining condition, grey relation analysis (GRA) and analysis of variance (ANOVA) were used. In conclusion, the best performance parameters for MRR, overcut and multiple characteristics of the orthogonal array were observed and predicted improvements are calculated in this paper.

PARAMETRIC EFFECTS AND ANALYSIS OF ELECTRO-DISCHARGE MACHINING OF TI-6AL-4V TITANIUM ALLOY

The present experimentation focused on investigating electro-discharge machining performance such as material removal rate, surface roughness, electrode wear, overcut, and hardness during machining of biomedical titanium alloy Ti-6Al-4V. Taguchi L25 array is used to determine the process input parameters combination for conducting the experiments. The process input parameters are pulse current, gap voltage, pulse on-time, and pulse off-time. The response surface methodology is used for mathematical modeling. Parameters are selected so uniquely that the properties of the machined components are affected dimensionally significantly less, at the same time rate of production is also reasonably high. The mathematical models are found to be satisfactory. After performing the extensive experimentations, the effect of specific parameters and microstructure was studied and analyzed. Electric-discharge machining of Ti-6Al-4V with precise control over individual response characteristics is simple. However, achieving simultaneous control on all performance characteristics (MRR, SR, EW, OC, and H) is complex. Microstructural analysis reveals that the surface texture of the machined impressions contains a relatively high proportion of black spots. These black spots produce a coarser surface having surface roughness value, Ra = 9.735 µm at 21 Amp pulse current, gap voltage 60 Volt, pulse on-time 350 µs, and pulse off-time 175 µs. However, the material removal rate is maximum at 0.086 mm3/min at these parameters. Dimensional accuracy in overcut OC is 0.118 µm with electrode wear of 0.0006 mm3/min, and alteration in the surface hardness is about 10 VH.

Effect of powder concentration on the EDM performance of AISI 304 using cryotreated post tempered electrodes

Powder mixed electro discharge machining (PMEDM) is a hybrid machining process in which dielectric fluid is mixed with electrically conductive powder particles for enhancing surface quality and material removal rate. Cryogenic treatment was brought in this process to improve tool life and cutting tool properties. In this research, silicon carbide (SiC) powder mixed electro discharge machining (EDM) has been performed for AISI 304 machining. Experiments have been carried out to study the effect of powder concentrations (0 g/l, 4 g/l, 6 g/l, 8 g/l and 10 g/l) on the EDM performances viz. radial overcut (ROC), material removal rate (MRR), surface roughness (Ra) and tool wear rate (TWR) using three tungsten carbide electrodes (i.e. untreated, cryotreated single and double tempered). With addition of powder concentration material removal rate, radial overcut enhances and surface roughness and tool wear rate reduces. With the addition of powder concentration MRR, TWR, Ra and ROC decreased up to 10.60%, 37.08%, 15.95% and 9.31% for cryotreated single tempered electrode and decreased up to 16.64%, 42.10%, 26.58% and 12.19% for cryotreated double tempered electrode respectively. Microstructural analysis of machined surface has been carried out for the PMEDMed surfaces.

Performance analysis of copper-based MWCNT composite coated 316L SS tool in electro discharge machining

The tool material properties are essential key factors for the enhancement of electro discharge machining performance mainly, resistance to the wear of tool, removal of material from workpiece, and machined surface quality. In this study, copper-based multi-wall carbon nanotube (MWCNT) composite coated 316 L stainless steel electrode was fabricated by electrodeposition method and used in EDM operation for investigating machining performance. The agglomeration problem of MWCNTs was a critical issue for fabrication copper matrix composite, which was addressed with a cationic dispersing agent. The copper-based MWCNT composite coated electrode was used for machining of 304 SS workpiece. The experimental results show 57.11% reduction of tool wear rate (TWR) and 99.52% improvement of material removal rate (MRR) for copper-based MWCNT composite coated electrode compared to pure copper coated 316 L SS electrode. The enhancement of surface quality was also observed for the machined surface, which was generated during the machining with copper-based MWCNT composite coated electrode. The micro-crack formation was almost eliminated by using copper-based MWCNT composite coated electrode, which will enhance the strength and fatigue property of machined component. The enhancement of micro-hardness was also observed for the machined surface.

Enhancement of EDM Performance by Using Copper-Silver Composite Electrode

Discharge Machining is a non-traditional machining technique and usually applied for hard metals and complex shapes that difficult to machining in the traditional cutting process. This process depends on different parameters that can affect the material removal rate and surface roughness. The electrode material is one of the important parameters in Electro –Discharge Machining (EDM). In this paper, the experimental work carried out by using a composite material electrode and the workpiece material from a high-speed steel plate. The cutting conditions: current (10 Amps, 12 Amps, 14 Amps), pulse on time (100 µs, 150 µs, 200 µs), pulse off time 25 µs, casting technique has been carried out to prepare the composite electrodes copper-sliver. The experimental results showed that Copper-Sliver (weight ratio70:30) gives better results than commonly electrode copper, Material Removal Rate (MRR) Copper-Sliver composite electrode reach to 0.225 gm/min higher than the pure Copper electrode. The lower value of the tool wear rate achieved with the composite electrode is 0.0001 gm/min. The surface roughness of the workpiece improved with a composite electrode compared with the pure electrode.

Powder-mixed electro-discharge machining performance of Inconel 718: effect of concentration of multi-walled carbon nanotube added to the dielectric media

The present work reports an experimental investigation on Powder-Mixed Electro-Discharge Machining (PMEDM) of Inconel 718 superalloy using Multi-Walled Carbon Nanotubes (MWCNTs) dispersed in kerosene, as dielectric media. Effects of variation of peak discharge current along with concentration of carbon nanotubes in the dielectric fluid are studied in purview of machining performance indicators including material removal efficiency, tool wear rate, and surface integrity of the machined part. The obtained results are compared to that of conventional EDM which utilizes kerosene as dielectric media. Morphology and topography, these two aspects of machined surface integrity are deliberated. The following surface morphological features: uneven fusion structure, globules of debris, molten metal deposition, surface cracks, pockmarks, and recast layer are identified. Topographical study includes surface roughness, severity of surface cracking, recast layer thickness, transfer of foreign elements, surface metallurgical characteristics, residual stress, and micro-indentation hardness. It is observed that application of MWCNT mixed dielectric media substantially improves EDM performance of Inconel 718 over conventional EDM. This is due to excellent thermo-physical properties of carbon nanotubes.

Analysis of EDM Process Parameters on Inconel 718 Using the Grey-Taguchi and Topsis Method

Nickel-based superalloys are gaining importance for their growing usage in aerospace industries. Amidst the various advanced machining processes, electro discharge machining (EDM) is considered to be an important one for its ability to machine materials irrespective of its intrinsic properties. In this study, Inconel 718 is considered as a work material, and an L18 orthogonal array (OA) experimental plan is utilized to machine the work material. The influential factors, which affect the EDM performance characteristics, are identified using analysis of variance (ANOVA). Not much work has been done regarding using grey-Taguchi technique for order of preference by similarity to ideal solution (TOPSIS) methods, although these methods can be easily applied for multi-objective optimization. These methods provide the best results with the available sparse data. The best combination of machining factors is determined using grey-Taguchi and TOPSIS methods. Based on the conducted experiments, voltage (V) and pulse off-time (t_off) show a notable contribution on output performance. The optimal combination of input parameter through grey-Taguchi is found to be 10 A, 30 V, 200 μs, and 20 μs respectively, for the EDM parameters: current (I), V, pulse on-time (t_on) and t_off for improved response. Moreover, the best parameter setting (I = 10 A, V = 30 V, t_on =100 μs and t_off = 20 μs) is identified using the TOPSIS method for the performance measures machining rate (MR), tool wear rate (TWR), overcut (OC), and taper overcut (TOC). Further tool wear behaviour is also studied through scanning electron microscope (SEM) images by varying the voltage.

Electro-Discharge Machining Performance of Nimonic 80A: An Experimental Observation

The present work reports electro-discharge machining (EDM) performance of superalloy Nimonic 80A. Experiments are conducted using a two-factor three-level full factorial design of experiment in consideration with two important electrical parameters: peak discharge current and pulse-on duration. Machining performance is evaluated in purview of material removal efficiency, rate of electrode wear, and surface integrity of the EDMed part product. Apart from morphological study, surface topographic measures including surface roughness, impact of surface cracking, white layer thickness, material migration, phase alteration, and micro-indentation hardness are studied in detail. Results of qualitative analysis on crater morphology are correlated with roughness value of the machined specimen. Effects of peak current and pulse-on time on influencing EDM performance indicators are also reported. An optimal parametric combination is determined for superior process performance. In doing so, utility theory is utilized to aggregate multi-performance characteristics to compute a unique index (called overall utility degree). The parametric combination which corresponds to maximum overall utility is assumed to be the best. It is determined that maximum material removal efficiency, minimal tool wear rate, and superior surface finish can be achieved at parameters setting: Ip = 35 A and Ton = 1000 µm. The said optimal setting corresponds to overall utility value of 6.53. Confirmatory test result yields: MRR = 9.05 × 10−3 g/s, TWR = 1.2 × 10−5 g/s, and Ra = 14.1 µm at optimal setting.

EDM performance of Inconel 718 superalloy: application of multi-walled carbon nanotube (MWCNT) added dielectric media

Electro-discharge machining (EDM) is very promising non-traditional machining route to cut ‘difficult-to-machine’ materials like Inconel 718 superalloy. However, low material removal efficiency and inferior surface integrity restricts EDM application on Inconel 718. In order to improve EDM performance, multi-walled carbon nanotube (MWCNT) dispersed into kerosene is explored as dielectric media. Experiments are conducted by varying peak discharge current with a fixed concentration of MWCNT (0.5 g/l) added to kerosene. EDM performance is assessed in purview of material removal efficiency, tool wear rate, and surface integrity (morphology and topography) of the EDMed specimen. Apart from morphological study, surface topography including surface roughness, crack density, recast layer thickness, metallographic alteration, residual stress, and micro-indentation hardness of the machined specimen are studied in detail. It is concluded that as compared to conventional EDM, use of MWCNT-mixed dielectric media (0.5 g/l) significantly improves machining performance.

Superior advance research in the electro-discharge machining of Ti alloys: Review

Electro Discharge Machining (EDM) known as an advanced machining process that much used for machining material with any hardness and complexity geometry in a high level of the accuracy in the cases of demand of the industrial application. The conception of the EDM process is included in applying electro-thermal energy in the gap, by discharge electrical power on the breaking point of the dielectric without any contact between electrodes. Due to the existing ability for removing debris from the surface, there is a lot of metallurgy defect on it. To improve and optimize EDM performance, the machine’s operating parameters, Input, during& output parameters, need to be optimized. Another handy way to reform of the view metallurgical must take picture sub-structure from the initial and subsequent layer. At the end for catching special status, adjust the technical parameters with metallurgical defects. Studies in case of the EDM have indicated that the appropriate selection of the way to control of the process, material, and operating parameters had considerably improved the process performance and also causing to was better the quality machined surface. This paper made a comprehensive review of the research studies in a different section of the EDM of various grades of titanium and its alloys. This review presents the simulation, experimental and theoretical studies on EDM that helped to improve the process performance, including material removal rate, surface quality, and tool wear rate, the stability of process among others. However, here are collected most of the research are done surrounding of EDM of Ti alloys as the developments of EDM and are seen material for future.

Selection of appropriate powder-mixed dielectric media (kerosene and used transformer oil) for desired EDM performance on Inconel 718 super alloys

Abstract In this reporting, application potential of copper powder added kerosene dielectric media has been compared to that of copper powder added used transformer oil (as dielectrics) during Electro-Discharge Machining (EDM) of super alloy Inconel 718. Improvement in machining performance of Inconel 718 has been studied in purview of machining rate, EDMed surface morphology as well as topography. The following topographical measures viz. roughness average, intensity of surface cracks, thickness of the white layer developed over the EDMed surface have been analysed. EDS and XRD analysis have been conducted to understand the extent of foreign element migration, formation of intermetallic phases, grain refinement taking place during the machining process. The comparative experimental study has finally concluded that copper powder mixed used transformer oil has been the better choice between aforesaid two alternative Powder-Mixed Electro-Discharge Machining (PMEDM) routes in view of machining performance of Inconel 718.

Experimental studies on graphite powder-mixed electro-discharge machining of Inconel 718 super alloys: Comparison with conventional electro-discharge machining

Inconel 718 is a nickel-based super alloy widely applied in aerospace, automotive, and defense industries. Low thermal conductivity, extreme high temperature strength, strong work-hardening tendency make the alloy difficult-to-cut. In contrast to traditional machining, nonconventional route like electro-discharge machining is relatively more advantageous to machine this alloy. However, low thermal conductivity of Inconel 718 restricts electro-discharge machining from performing well. In order to improve the electro-discharge machining performance of Inconel 718, powder-mixed electro-discharge machining was reported in this paper. It was carried out by adding graphite powder to the dielectric media in consideration with varied peak discharge current. The morphology and topographical features of the machined surface including surface roughness, crack density, white layer thickness, metallurgical aspects (phase transformation, crystallite size, microstrain, and dislocation density), material migration, residual stress, microindentation hardness, etc. were studied and compared with that of the conventional electro-discharge machining. Additionally, effects of peak discharge current were discussed on influencing different performance measures of powder-mixed electro-discharge machining. Material removal efficiency and tool wear rate were also examined. Use of graphite powder-mixed electro-discharge machining was found to be better in performance for improved material removal rate, superior surface finish, reduced tool wear rate, and reduced intensity as well as severity of surface cracking. Lesser extent of carbon migration onto the machined surface as observed in powder-mixed electro-discharge machining in turn reduced the formation of hard carbide layers. As compared to the conventional electro-discharge machining, graphite powder-mixed electro-discharge machining exhibited relatively less microhardness and residual stress at the machined surface.