Non-traditional Machining Technique Research Articles

Research on machining Technology of Electrospark-electrochemical Hybrid Energy Field with tungsten hole

The machining technology for tungsten hole faces considerable challenges. Electrical Discharge Machining (EDM), as a non-traditional machining technique, is widely applied due to its capability to process conductive materials. This technique is characterized by high precision metal processing, high material removal rate, and low tool wear rate. Molecular dynamics simulation technology is employed in this study to model the single pulse discharge process, with the aim of elucidating the erosion mechanism of different melting point metal materials in the melt pool during spark discharge and the effect of pressure difference inside and outside the melt pool. Moreover, for the efficient machining of tungsten materials, Electrospark-electrochemical Hybrid Energy Field Machining (ECEM) method is proposed, which is conducted under a certain conductivity salt solution. The simultaneous high-speed electric spark discharge and electrochemical action effectively promote the rapid formation of spark plasma discharge channels. Orthogonal experimental data and images are utilized in this paper to study the machining of tungsten micropores, with the effects of pulse width, pulse interval, peak current, and concentration of NaNO3 being analyzed, and the optimal machining parameters being determined.

Experimental investigations on coated copper wire and annealed copper wire electrodes in wire EDM machining through a comparative assessment employing the TOPSIS technique

Metals that are electrically conductive but are difficult to work with are typically machined using WEDM (Wire Electric Discharge Machining). The production of tiny components, which are challenging to mill using earlier non-traditional machining techniques, has undergone a substantial transformation thanks to these machines. Two wire electrodes coated copper wire and annealed copper wire electrodes are used for the testing in this investigation, and the analysis is completed utilizing the tool material. The workpiece material, D2 Steel, was cut into cubes that were 10 mm thick for the experiment, and a wire electrode with a diameter of 0.25 mm was used. Using an L27 orthogonal array, six input variables were employed at three different levels in the testing. The TOPSIS technique is utilized to optimize the output variables, leading to the determination of various output parameters, including Material removal rate (MRR), Kerf width (KW), tool wear rate (TWR), and surface roughness (SR). The chosen input variables include wire tension (WT), a gap voltage (GV), input current (IP), wire feed rate (WF), pulse off time (Toff), and pulse on time (Ton). The 10 mm-wide D2 steel was milled using two wire electrodes, and an ANOVA table was made to identify the factors that had the greatest impact on the WEDM parameters. The rank and ideal Wire EDM parameter values must be calculated using main effect plots and tables of replies. From this investigation, we can also draw the conclusion that for machining D2 steel, annealed wire electrodes provide greater MRR than coated wire.

Minimization of residual stress, surface roughness and tool wear in Electro Discharge Machining of inconel 625

Electro Discharge Machining (EDM) is a well-known non-traditional machining technique which is widely used to make die castings and turbine blades out of difficult-to-cut materials like Inconel 625. The machined part's surface quality and dimensional accuracy are affected by the EDM electrode's wear. Moreover, surface roughness and residual stress augmentation of EDM-machined components can reduce the workpiece's lifespan by decreasing the fatigue life of machined parts. To enhance the precision and durability of EDM machined components, residual stress, tool wear, and surface roughness should be evaluated and minimized. The majority of published research works for the assessment and optimization of EDM machining parameters are based on experimental works which are limited to testing, workpiece materials, and machining conditions. In order to improve the quality of machined surfaces and reduce tool wear and residual stress during Inconel 625 EDM processes, a virtual machining approach has been developed in the research work. To predict the cutting temperature during EDM operations, the modified Johnson Cook model of Inconel alloys is used. The finite element approach is then used to calculate the generated residual stress during the EDM process. The proposed virtual machining approach is also applied in order to predict the surface roughness of EDM machined parts. To minimize the residual stress, tool wear, and surface roughness during EDM operations of Inconel 625, the machining parameters of gap voltage, peak current, pulse-off time, and pulse-on time are optimized using the Taguchi optimization approach. Experiments and simulations are then conducted to verify the developed virtual machining system in the study. So, using the optimal machining parameters, the residual stress, surface roughness of machined items and wear of EDM electrode are minimized by 24.5 %, 25.4 %, and 25.4 % respectively. Thus, the quality and reliability of components made using EDM processes may be enhanced by the suggested virtual machining system.

Numerical investigation on design parameters of orifice plate for positioning of workpiece in cavitation zone for cavitation machining

ABSTRACT The recent development of non-traditional machining techniques, such as cavitation machining (CM), has been gaining traction amongst researchers due to its sustainable nature. The present research focuses on the use of computational fluid dynamics (CFD) model to predict the location of workpiece in the fluid domain and bubble distribution during CM process. For efficient CM, the correct positioning of a workpiece in cavitation zone is essential, as the implosion of the cavity bubble leads to formation of micro-jet and shock waves for a few milli-to-microseconds generating high temperature and pressure on workpiece. The aim is to harness cavitation phenomena in material processing, particularly by using orifice plates as a common tool to induce hydrodynamic cavitation. To generalise the investigation, the flow simulation through orifice plate with different aspect ratios (l/d) are carried out. For the bubble distribution and their diameters, the Lagrangian discrete phase model (DPM) is used in the downstream side of the flow domain. Using this information, bubble dynamics have also been investigated using the Keller–Miksis (KM) model to compute the implosion time and intensity in the zone. The presented exploration determines the orifice dimensions to optimize implosion intensity, ensuring precise workpiece placement in real-time CM.

Developments, challenges and future trends in advanced sustainable machining technologies for preparing array micro-holes.

The use of array micro-holes is becoming increasingly prevalent across a range of industries, including the aerospace, automotive, electronics, medical and chemical industries. The utilization of advanced sustainable machining technologies offers distinctive advantages and is pivotal for the sustainable manufacture of array micro-holes. This paper examines the sustainable machining techniques commonly employed in the production of array micro-holes, including electrical discharge machining, laser machining, electrochemical machining and composite machining technologies. The paper begins with an elaboration of the processing principles and characteristics of multiple non-traditional machining techniques. The performance indicators of the most commonly used processing technologies in industrial production are summarized from seven perspectives. Six significant avenues for the advancement of sustainable manufacturing technology for array micro-holes have been identified and categorized. This article provides a summary and evaluation of the previous relevant literature, with the aim of offering guidance for the development of array micro-hole processing technologies.

Surface modification by electrical discharge machining: A systematic literature review and bibliometric analysis

In past few decades, the non-traditional machining techniques of electrical discharge machining (EDM) has been developed to machine materials that are difficult to cut. Additionally, the EDM method has also been employed to change the material's surface properties by applying a layer on the workpiece that is up to a few microns thick in order to improve the surface attributes. In past three decades, several numerous investigations on surface modification using EDM have been conducted globally. Present study provides a comprehensive review along with bibliometric investigation of the many approaches used to enhance the surface topology of the materials during the EDM process from 1993 to 2023. Firstly, a brief introduction to EDM-based different surface modification techniques such as electric discharge coating, surface texturing, surface alloying, and powder-mixed EDM has been given. All related documents were acquired from Scopus Core Collection and evaluated using a bibliometric analysis technique. The bibliometric analysis was examined based on the time distribution of articles, geography, top-cited documents, analysis of authors’ keywords, country-wise publications, etc. The result showed that India dominates this research area, followed by China, and there is a growing trend in the number of publications. Further, the influence of EDM parameters, dielectric fluid, tool, and work material etc. has also been discussed. The research work published related to topic has been summarized and resented in tabular format. This review offers interested scholars with a thorough overview of the significant achievements in the subject over the last few decades, including a description of the most relevant studies and their results. Moreover, potential areas for further investigation are emphasized with the goal of revitalize the interest of the worldwide scientific community in advancing this method.

EFFECT OF ZINC COATED BRASS AND LN2 COOLED ZINC COATED BRASS ELECTRODES IN WEDM PERFORMANCE ON INCOLOY

Due to their superior mechanical qualities, such as corrosion resistance and carburization resistance, particularly at high temperatures, nickel-based superalloys are being used more often in the aviation, marine, and nuclear industries. Because of their great strength, low heat conductivity, and strain hardening properties, nickel-based superalloys are particularly difficult to process conventionally. Wire electric discharge machining, one of the non-traditional machining techniques, is utilised in this study to cut Inconel 800. (Incoloy). Wire cut EDM uses electrodes made of zinc-coated brass wire that have been cryogenically chilled. The RSM approach is used to arrange trials using Servo voltage and Wire feed as constant variables and Wire tension, Pulse on time, and Wire feed as changeable factors. In order to maximizes responses, lower is better and higher is better criteria are used to assess material removal and surface roughness for zinc-treated brass and cryogenically chilled (LN2) zinc-treated brass.

Optimization of wire-EDM process parameters for Ni–Ti-Hf shape memory alloy through particle swarm optimization and CNN-based SEM-image classification

Shape memory alloys (SMAs) have the unique ability to regain their shape under specified conditions, making them extremely useful for a wide range of applications. However, non-traditional machining techniques could be more effective for high-temperature SMAs as they provide better shape recovery properties than conventional methods, necessitating this study's unconventional wire electric discharge machining procedure. The surface morphology of Ni–Ti-Hf-based alloys was examined using scanning electron microscopy. A convolutional neural network model was used to categorize SEM images based on the material removal rate, utilizing the pixel intensity histogram of the processed images. The study discovered that the material remelted as the discharge energy increased, leaving lumps and globules on the surface. The size of debris lumps, pores, and globules increased with increasing Ra values. Moreover, widening the inter-electrode gap by expanding the servo-voltage facilitated efficiently removing debris from the machined site. The TOPSIS method for particle swarm optimization was employed to find the optimal solutions, yielding TON = (124.239, 116.228), TOFF = (54.532, 40.781), Servo voltage = (36.216, 43.766), and Wire-Feed = (2.157, 8). These results were validated through experimentation, with minimal error percentages of 2.01%, 2.046% (MRR), and 3.86%, 1.611% (Ra) for both sets of input parameters, respectively.

Investigation study of electrical discharge machining parameters on material removal rate for AISI M2 material

EDM (Electrical Discharge Machining) is a common non-traditional machining technique for manufacture geometry parts made of intricate or extremely rigid metals that are challenging to manufacture using conventional manufacturing techniques. Electrical discharge machining by utilizing electrical discharge erosion, classify the meaning of material removal (MR). This paper's main objective is to discuss the ideal EDM parameters in order to use high-speed steel as workpiece AISI M2 and with using brass & copper as electrodes. Pulse on-time are (100, 150, and 200 µs), Current (10, 24 and 42 A) and Pulse off-time (4, 12 and 25 µs) are the input parameters effect on the material removal rate (MRR) used in the experimental work. The present study's findings shown that the highest MRR with using copper & brass as electrodes with pulse on-time 200 µs, pulse off-time 12 µs and current 42 A, at (0.31284 g/min and 0.18769) respectively, and the lowest average value of the removed material was when evaluating current 10 A, Ton is 100 µs, Toff is 4 µs, at (0.05451g/min and 0.01898 g/min) respectively.

Micromachining of predesigned perpendicular copper micropillar array by scanning electrochemical microscopy

Because the electrochemical reactions can occur gently at normal temperature and pressure, electrochemical micromachining (ECMM) is an important nontraditional precision machining technique free of tool wear, heating effect, residual stress, surface and subsurface damage, comparing with the ultra-precision milling, electrical discharging machining, laser beam machining, etc. Although scanning electrochemical microscopy (SECM) has been proven powerful in ECMM, it is difficult to fabricate the predesigned perpendicular microstructures because of the inhomogenous potential distribution, the complex electrode reaction kinetics and the interfacial mass transfer processes. Here we succeeded in fabricating the copper micropillar arrays by combining the SECM direct-writing mode and the ultrashort voltage pulse (USVP) modulations. The machining accuracy and efficiency are affected by multiple technical parameters, including the amplitude, the period and the duty cycle of the USVP modulations, the components and concentration of the electrolyte solution, the tip-substrate distance, the motion mode of the tool electrode, etc. By employing multiple parameters central composite experimental designs, we succeed in optimizing the technical parameters and avoiding the complexities of electrode processes. The results demonstrate the powerful capability of SECM in the controllable micromachining of the perpendicular metallic microstructures.

Performance evaluation of CNN-based crack detection for electrical discharge machined steel surfaces

Electrical discharge machining (EDM) is a non-traditional machining technique that is frequently employed on hard materials. In today's industrial practice, it has been the most prevalent non-traditional material removal procedure. It allows you to process challenging materials and construct complicated forms with excellent accuracy. In the context of image pre-processing approaches to discover defective or non-defective machining pieces through EDM, the Centre of attention of this article is utilizing convolutional neural networks (CNN) to create a machinery piece defective detection approach. A total of 180 datasets of varying sizes produced from public datasets, the proposed CNN model is assessed and compared to pre-trained networks, namely the VGG-16, VGG-19, ResNet-50, and ResNet-101 models. The assessment took into crack detection outcomes, and classification parameters such as accuracy, precision, recall, and F1-score. Also, we have given the receiver operating characteristic (ROC) curve, precision–recall curve, and confusion matrices for each model for the required classification to predict the defective cracks, and also, we included the histograms to find the probabilities of defective and non-defective cracks. The suggested model can discriminate between pictures that are cracked and those that are not. According to the findings, VGG-16 has the best accuracy out of all of these models. In comparison to prior conventional procedures, the proposed EDM crack defective detecting methodology gives great accuracy.VGG-16 attains 93% accuracy, 93% of F1-score, 94% of precision, 93% of recall, 93% of specificity, as well as 97% of AUC, testing findings suggest that our strategy is capable of incredible performances.

An Integrated RSM - improved salp swarm algorithm for quality characteristics in AWJM of Ananas comosus-HIPS composites

Natural fiber based polymer composite materials are increasingly used in wider applications due to their low weight and improved mechanical qualities. However, due to their inherent heterogeneity, anisotropy, and temperature sensitivity, traditional machining of composite materials is difficult. Abrasive water jet (AWJ) cutting is a non-traditional machining technique that has recently been used to fabricate polymer matrix component parts. Therefore, this study focuses on the machinability of ananas comosus–high impact polystyrene composites (each wt50%) using the AWJ process. The experiments were conducted and analyzed using central composite design (four-factor, five-level) and the response surface methodology, respectively. The mathematical models between process parameters, kerf inclination, entry delamination factor (DF) and exit DF were established and confirmed by verification. Analysis of variance was utilized to examine the influence of each input parameter on the responses. The AWJ machined surfaces were examined using a SEM images. Further, the developed models were coupled to the improved salp swarm algorithm, which was used to find the best cutting parameters for the minimizing of kerf inclination, entry DF, and exit DF, which are all important quality aspects. During the confirmatory tests, only minor differences (less than 2%) between the predicted and experimental results were observed.

Non-Traditional Machining Techniques in Manufacturing Industries – An Overview

This comprehensive study provides an in-depth analysis of non-traditional machining techniques in the manufacturing industry. Focusing on mechanical, electrochemical, chemical, and thermal machining processes, the research explores recent advancements and their implications. The study adopts the action research method to gain a deeper understanding of the challenges associated with these techniques. Through a thorough examination of the machining processes, this work delves into various concepts, including the operations involved in each process and their corresponding outcomes. The analysis sheds light on the significance of non-traditional machining in the manufacturing industry, highlighting its potential for producing complex components and meeting design requirements that traditional machining methods may struggle to achieve. By exploring recent developments in non-traditional machining, this study aims to provide an overview of the advancements made in this field. It emphasizes the importance of understanding these techniques to unlock their full potential and enhance manufacturing capabilities. The findings of this research contribute to the existing knowledge base and serve as a valuable resource for professionals and researchers in the field of non-traditional machining.

A review on the physical and mechanical properties of natural fiber reinforced composites and its machinability using abrasive waterjet machining

In recent years greater concern is being shared between different research and engineering communities for developing eco-friendly engineering materials. Natural fiber reinforced composites (NFRC) are one of the highly explored materials which are drawing the interests due to the numerous advantages they offer. Today most of the research are focused on replacing the synthetic fibers by natural fibers as they are abundant, lower cost, biodegradable and show good mechanical properties. The NFRC are majorly used in automobile, aerospace and civil applications. One of the problems associated with natural materials is their machinability. The traditional machining of NFRC poses various challenges such as delamination, lower precision, cracks, higher surface roughness etc. Therefore, it is necessary to identify sustainable machining techniques for natural materials. Abrasive waterjet machining (AWJM) is one of the most viable non-traditional machining methods and its efficiency in machining NFRC is higher compared to other non-traditional machining techniques. Therefore, in this article a detailed review is conducted to understand the different natural fibers utilized for the fabrication of composite. Also, their mechanical properties (MP) and applications in different industries are detailed. In addition, the effect of AWJM parameters on the machinability of NFRC and optimum process parameters for achieving better machining quality in NFRC are discussed.

Non-traditional machining techniques for silicon wafers

Silicon (Si) micromachining techniques have recently witnessed significant advancement, attributable to the high surge in demand for microelectromechanical and microelectronic devices. Micromachining techniques are widely used to cut or pattern Si, in order to obtain high-quality surface finishes for the fabrication of devices. Micromachining techniques are used for the fabrication of three-dimensional (3D) microstructures for microelectromechanical devices. In this work, the capabilities and competencies of non-traditional Si micromachining techniques, including ultrasonic, ion beam milling, laser machining, and electrical discharge machining, are discussed and compared accordingly. The working principles, advantages, limitations, and Si microstructures that have been fabricated before are discussed in detail. Additionally, this work covers the performance reported by multiple researchers on these micromachining methods, spanning the temporal range of 1990 to 2020. The key outcomes of this study are explored and summarized.

Optimization of EDM process parameters for TWR on machining of Inconel 600 superalloy using Taguchi approach

Electrical discharge machining (EDM) is a non-traditional machining technique that is commonly employed on hard materials. The fact that EDM can cut any conductivematerial, independently of its hardness, has made it popular. EDM is extensively used to shape or create advanced technological materials which are used in extreme conditions. The effects of input parameters on the effective machining of Inconel 600 superalloy was investigated in this study. The tool electrode was made of Tungsten Carbide (WC), and the dielectric fluid was EDM oil. The Taguchi method was used to investigate the effects of control factors including pulse-on-time (Ton), peak current (Ip), and gap voltage (Vg) on the performance criterion TWR. Using an orthogonal array (OA) L9, the research were carried out at three levels. The EDM performance aspects were investigated using the signal-to-noise ratio and ANOVA. The Taguchi technique was used to optimize the input and output parameters using the statistical software MINITAB-17. During the EDM process, TWR grows somewhat linearly with increasing Ip. TWR reduces as Vg increases, then increases as Vg increases. TWR increases with increasing Ton and then drops with increasing Ton. The tool wear rate is lowest at the first level of Ip, the second level of Vg, and the third level of Ton. ANOVA revealed that Ip, Vg, and Ton all had a significant influence on TWR. Obtained optimum input variables value for tool wear rate are Ip (30 A), Vg (94 V), and Ton (150 s). The predicted ideal range of TWR at 95% confidence level was confirmed by conducting confirmation experiments, wherein the TWR was achieved as 0.551 mm3/min. To validate Taguchi's optimization approach, confirmation tests were performed using optimal values of input parameters.

Challenges in abrasive jet machining of fiber-reinforced polymeric composites – a review

PurposeThe purpose of this study is for solving many issues in production that includes processing of complex-shaped profile, machining of high-strength materials, good surface finish with high-level precision and minimization of waste. Among the various advanced machining processes, abrasive jet machining (AJM) is one of the non-traditional machining techniques used for various applications such as polishing, deburring and hole making. Hence, an overview of the investigations done on carbon fiber-reinforced polymer (CFRP) and glass fiber-reinforced polymer (GRFP) composites becomes important.Design/methodology/approachDiscussion on various approaches to AJM, the effect of process parameters on the glass fiber and carbon fiber polymeric composites are presented. Kerf characteristics, surface roughness and various nozzle design were also discussed.FindingsIt was observed that abrasive jet pressure, stand-off distance, traverse rate, abrasive size, nozzle diameter, angle of attack are the significant process parameters which affect the machining time, material removal rate, top kerf, bottom kerf and kerf angle. When the particle size is maximum, the increased kinetic energy of the particle improves the penetration depth on the CFRP surface. As the abrasive jet pressure is increased, the cutting process is enabled without severe jet deflection which in turn minimizes the waviness pattern, resulting in a decrease of the surface roughness.Research limitations/implicationsThe review is limited to glass fiber and carbon fiber polymeric composites.Practical implicationsIn many applications, the use of composite has gained wide acceptance. Hence, machining of the composite need for the study also has gained wide acceptance.Social implicationsThe usage of composites reduces the usage of very costly materials of high density. The cost of the material also comes down.Originality/valueThis paper is a comprehensive review of machining composite with abrasive jet. The paper covers in detail about machining of only GFRP and CFRP composites with various nozzle designs, unlike many studies which has focused widely on general AJM of various materials.

Effect of Tool Geometry on the Machining Characteristics amid SiC Powder Mixed Electric Discharge Drilling of Hybrid Metal Matrix Composite

The manufacturing of hybrid metal matrix composites (HMMCs) combines two or more reinforcing materials exhibiting distinct properties, with a steady metal matrix phase. Such combinations display improved mechanical properties and abilities to potentially satisfy the needs of progressive engineering applications. However, non-traditional machining techniques are required for the adequate subtractive manufacturing of HMMCs for the specific purposes. In this research, powder mixed electric discharge drilling (PM-EDD) of Al6063/ 5% SiC / 2.5% Gr / 2.5% Al2O3 HMMC was performed with tool electrodes of dissimilar geometries at 5 g/l silicon carbide (SiC) powder particle concentration. A set of solid conical and hollow cylindrical tool electrodes made up of quenched copper, were used in the present work. Discharge-current, duty-factor, tool-speed, and flushing-pressure were chosen to be the governing input control variables. The performances of the two tool electrodes were experimentally examined and compared in terms of material removal rate (MRR), tool wear rate (TWR), and surface roughness (SR) during PM-EDD of the HMMC. However, material removal rate (MRR) was considered to be the foremost benchmark for the comparative analysis of the two tool electrodes. An implementation of response surface methodology (RSM) was executed to optimize the responses. The hollow cylindrical tool electrode could achieve 33.79% higher MRR as compared to solid conical tool electrode. The results displayed that the discharge-current had the most remarkable influence on the PM-EDD process compared to other input control variables.

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.

Process parameter optimization of abrasive water jet machining on monel k400 alloy

Nowadays it’s difficult to use a metal with high corrosion resistant properties in required applications. Monel 400 is one nickel based alloy having required property to be applicable in such scenarios. It is used in highly corrosive environments such as marine, chemical and aerospace industries as it has the property of maintaining its toughness over a range of temperature, however machining of this Monel alloy is relatively tough due to its characteristic work hardening properties. To tackle the mentioned issues, Abrasive water jet machining is used which is a widely known nontraditional machining technique. The process parameters and the response variables were chosen depending on the machine specifications, and parameter combinations were made using Minitab statistical software. The parameters and their interactions like the cut quality on the alloy, nozzle diameters effects, and water pressure were also studied. Response surface model and various statistical algorithms such as S-N ratio, ANOVA and regression equations were utilized for formation of the design of experiment, optimization of process parameters for the machining process were done using Grey relations. Reduction of surface roughness, maximization of Material removal rate while simultaneously reducing the cycle time for the operation was the primary objective. The results thus obtained indicates that the quality of cut was the most influential factor in the machining process followed by water-jet pressure value.