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The exploration of Electrical Discharge Machining (EDM) with coated electrodes represents a relatively novel research avenue, thereby yielding limited published research outcomes. The choice of coating material plays a pivotal role in the EDM machining process, and alterations in coating materials can directly influence the adjustment of technological parameters in EDM. Consequently, research dedicated to optimizing these technological parameters for EDM employing coated electrodes is of paramount importance, and it promises to advance the practical implementation of this cutting-edge technique. In this study, we systematically investigate the technological parameters for EDM employing a copper-coated aluminum electrode in the context of Ti-6Al-4V machining. Our research outcomes are framed within a multi-objective optimization paradigm, with a focus on Material Removal Rate (MRR) and Surface Roughness (SR) as vital quality indicators. To address the intricate multi-objective optimization challenge, we have harnessed the combined power of the Taguchi methodology and the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). The amalgamation of these techniques enables us to navigate the complexities of EDM parameter optimization effectively. Our findings reveal that the most favorable process parameters entail a configuration of U=40V, I=40 A, Ton=1000μs, resulting in an MRR of 0.028mg/min and an SR of 7.56μm. These optimized parameters exemplify a substantial enhancement in machining efficiency and surface quality when utilizing coated electrodes. Moreover, our study scrutinizes the quality of the machined surface under optimal conditions with coated electrodes. We employ the TOPSIS method as a proficient solution for this endeavor, offering a straightforward approach to this intricate calculation process. [ABSTRACT FROM AUTHOR]

This study investigates the performance of deep cryogenically treated brass (CuZn25Al5) electrodes in the die-sink EDM process. Two different cryogenic treatment durations, 6 h and 12 h, were applied to 8 mm diameter electrodes, and their effects were compared to untreated electrodes. The machining tests were conducted under moderate and aggressive conditions. In the machining tests, the 6-h cryo-treated electrode exhibited a 16.8% increase in material removal rate (MRR) under moderate conditions and a 19.7% increase under aggressive conditions compared to the reference electrode. The 12-h cryo-treated electrode showed similar MRR values to the reference electrode but improved tool wear resistance by 9.4% under moderate conditions. The kerf angle was minimized, indicating better hole verticality, in the 6-h cryo-treated electrode group. The improvement in machining performance was attributed to the enhancement in electrical conductivity of the electrodes, which increased by 28% for the 6-h cryo-treated electrode and 20% for the 12-h cryo-treated electrode. X-ray diffraction (XRD) analysis revealed shifts in peak positions and possible phase transformations due to cryogenic treatment. Surface roughness measurements showed improved surface conditions in the cryo-treated electrodes under aggressive conditions. The results indicate that cryogenic treatment enhances MRR, reduces tool wear, and improves surface quality in die-sink EDM. These improvements are attributed to increased electrical conductivity and changes in the internal structure of the brass electrode. [ABSTRACT FROM AUTHOR]

Electrical discharge machining (EDM) is widely applied for machining difficult-to-cut materials in mold and die industries. However, the major limitations associated with the EDM are low productivity and poor surface integrity of the machined surfaces. In recent years, several developments have been applied to overcome such limitations of EDM. Electrical discharge grinding (EDG) is a hybrid machining process that simultaneously involves the spark erosion action of EDM and the mechanical abrasion action of the grinding wheel for the material removal purpose. The rotating motion of the grinding wheel also contributes to the easy removal of debris particles, thereby improving the material removal. It is evident from the literature that the rotating motion of the grinding wheel enhances the flushing mechanism resulting in better performance of the process. This paper aims to present a comprehensive review of the research carried out in EDG, highlighting the result of the experimental, modeling, and optimization techniques applied in this area. Initially, the background of EDM and the need for hybrid EDM processes have been presented. Then, a few hybrid EDM processes have been discussed, addressing their advantages and limitations. Further, the concept of EDG and electrical discharge diamond grinding (EDDG) has been discussed, along with the classification of the EDDG process. Finally, this paper explores the current research status and future research perspective in the area of EDG and EDDG processes. [ABSTRACT FROM AUTHOR]

The electrical discharge machining (EDM) is an extremely effective manufacturing process to create deep and three-dimensional complex cavities. In EDM, machining occurs due to the generation of thermoelectric energy between the work piece and an electrode. EDM widely engaged for cutting superalloy material that are having high strength to wear ratio, corrosion resistance, etc. In this work, Inconel 825 material, which is nickel–chromium based superalloy, is opted due to its outstanding mechanical and thermal properties. We considered various important EDM input parameters, i.e. spark gap (Sg), gap voltage (Vg), pulse on time ( T on ), pulse off time ( T off ), peak current ( I p ), servo feed (Sf), depth of cut (Dc) and difficulty index (Di) with Taguchi L 2 7 orthogonal array for optimizing output responses, i.e. tool wear rate (TWR), material removal rate (MRR) and surface crack density (SCD) in multi-objective optimization (MOO) realm. Undertaking repeated experimental runs are very expensive, tedious, time consuming and economically unjustified. Hence, we have robustly introduced a novel integrated computational Taguchi based grey relational analysis (TGRA) accompanied with Taguchi based technique for order of preference by similarity to ideal solution (T-TOPSIS) to optimize the EDM process. This research represents that the pulse on time is the chief significant factor and the p value is found as 0.002 for both TGRA and T-TOPSIS. Experimentally, it has been confirmed that the optimum settings yielding an improvement of 0.01627 and 0.28071 in TGRA and T-TOPSIS score, respectively. The comparative analysis for the methodologies is fruitfully discussed and the results clearly present the effective parametric combinations to be implicated for optimizing MOO framework. Investigation of surface topography is fruitfully presented and the effects of the pulse on time, gap voltage and pulse off time on heat affected layers, machining debris and surface cracks were also discussed. Validation tests were carried out and show closer relationship with the experimental results. [ABSTRACT FROM AUTHOR]

Durable superhydrophobic aluminum alloy surfaces were prepared through a facile method: combining high-speed wire electrical discharge machining and chemical modification. Three types of pulse width were selected to machine the aluminum alloy surfaces with different levels of surface roughness. The effect of immersion time in perfluorooctanoic acid on the wettability of the aluminum alloy surfaces was examined. The contact angle of the superhydrophobic aluminum alloy surfaces was 1 5 9. 7 ± 3 ∘ , and the sliding angle was 1 ± 0. 5 ∘ . After sanding with coarse sandpaper, the aluminum alloy surfaces still exhibited superhydrophobicity with a stroke of 450 cm, indicating good mechanical durability. The prepared superhydrophobic aluminum alloy surface heated for 2 h within the 190–240∘C temperature range showed favorable thermal stability. In addition, the superhydrophobic aluminum alloy surface exhibited self-cleaning property. Therefore, the superhydrophobic aluminum alloy surface prepared by using the simple mass production method showed good mechanical stability, thermal stability, and self-cleaning property, as well as broad application potential. Superhydrophobic Al alloy surfaces were successfully prepared by HS-WEDM and chemical modification, with a CA of 159.7 ± 3∘ and a SA of 1 ± 0.5∘. The as-prepared superhydrophobic Al surface shows good mechanical durability because of the protection coming from the rough peaks. After being heated at 240∘C for 2 h, the superhydrophobic Al surface still had a CA of 153 ± 0.6∘ and a SA of 7∘ ± 0.8∘, indicating its satisfactory thermal stability. [ABSTRACT FROM AUTHOR]

Electrical discharge machining (EDM) is one of the most explored nonconventional machining processes due to its ability to machine intricate shapes on conductive materials. However, tool wear is one of the major challenges in the EDM process as it directly affects the accuracy of machining, surface roughness, reproduction of geometrical characteristics on the workpiece and cost of the process. Lots of work have been done to minimize the tool wear by improving the discharge conditions by controlling the EDM process parameters, varying the dielectric characteristics, powder-mixed dielectric methods and ultrasonic-assisted methods. However, minimizing the tool wear by the above approaches also constrains the material removal rate from the workpiece and accuracy of the process. This review highlights the efforts done by the researchers to improve tool wear by recently developed techniques or modifications. Researches available in the field of using treated tool electrode, cooled tool electrode, coated tool electrode, noble tool materials and other techniques are highlighted. [ABSTRACT FROM AUTHOR]