The material removal in EDM occurs due to the formation and collapse of a plasma channel between the electrode tool and workpiece. When a potential difference is applied, a spark is generated that reaches over 10,000°C, causing localized melting and vaporization of material. The plasma channel collapse then generates shock waves that remove the molten material. Proper dielectrics like kerosene are used to prevent oxidation and efficiently flush debris while maintaining the spark gap. Various power generators including RC relaxation circuits are used to control the electric spark discharge process parameters. EDM allows precision machining of electrically conductive materials, especially hard or complex shapes.
Electrical Discharge Machining (EDM) is a manufacturing process that uses electrical sparks to remove material from a conductive workpiece. In the EDM process, a tool electrode is moved close to the workpiece and an electric spark is generated via a dielectric fluid between them, vaporizing a small amount of material. This process is repeated many times to gradually shape the workpiece. EDM can machine very hard materials and complex shapes without causing mechanical stress to the workpiece. Common applications include drilling micro holes, cutting intricate profiles, and machining hardened steel dies and molds.
The document provides information on Electrical Discharge Machining (EDM). EDM is a manufacturing process where electrical discharges are used to erode material from a workpiece to achieve a desired shape. In EDM, a series of sparks erode material by rapidly recurring electrical discharges between two electrodes separated by a dielectric liquid and subject to an electric voltage. One electrode is the tool that shapes the workpiece. Material removal occurs through thermal melting and vaporization caused by the extreme heat of electrical sparks between the electrodes.
Electrical Discharge Machining (EDM) is a manufacturing process where electrical discharges are used to erode material from a workpiece to achieve a desired shape. In EDM, a potential difference is applied between an electrode tool and the workpiece, which are separated by a dielectric liquid. This causes electric sparks to form that melt and vaporize small amounts of material from both the tool and workpiece. Kerosene or deionized water is typically used as the dielectric liquid to facilitate flushing of debris and prevent oxidation during the process.
Electrical Discharge Machining (EDM) is a manufacturing process where electrical discharges are used to erode material from a workpiece to achieve a desired shape. In EDM, a series of electrical sparks are generated between two electrodes submerged in a dielectric liquid and subject to an electric voltage. This causes material to be removed from both electrodes through localized melting and vaporization due to the extreme heat of the sparks. EDM can be used to machine hard metals and intricate shapes that would be difficult to machine through conventional methods.
The document discusses Electrical Discharge Machining (EDM). EDM is a manufacturing process where a desired shape is obtained by removing material from a workpiece using electrical discharges between two electrodes separated by a dielectric liquid. As the distance between the electrodes is reduced, current flows due to dielectric breakdown causing material removal from both electrodes. EDM was invented in the 1940s and has since improved, increasing machining speeds and reducing costs. EDM can machine hard metals and intricate shapes without needing to soften the material. The main components of an EDM system are the power supply, dielectric medium, workpiece and tool electrodes, and servo control unit. Material is removed through the formation and collapse of plasma channels between the electrodes during
Here you are watching PowerPoint Presentation of EDM (Electrical Machining Process). It is a kind of unconventional machining process.Thanks for watching.
Electro Discharge Machining (EDM) is a non-traditional machining process that uses electrical sparks to remove material. In EDM, an electric spark is generated between an electrode tool and conductive workpiece submerged in a dielectric fluid. This spark removes microscopic amounts of material through thermal erosion. EDM can machine hard metals and complex shapes. It produces a recast layer on the workpiece surface with altered properties that may require post-machining treatment. Common applications of EDM include die and mold making.
Full details of Electroc discharge machine ,Ultrasonic machining, Electro Che...ManojSingh376471
This document provides information on three non-traditional machining processes: electric discharge machining (EDM), ultrasonic machining (USM), and electrochemical machining (ECM). EDM uses electric sparks to erode material away from a workpiece. USM employs abrasive particles and ultrasonic tool vibration to machine brittle materials. ECM removes metal from a workpiece using electrolysis with the workpiece as the anode. Key aspects of each process like operating principles, applications, and important process parameters are described. Diagrams illustrate EDM working, wire EDM, USM setup, and ECM principles.
Electrical Discharge Machining (EDM) is a manufacturing process that uses electrical sparks to remove material from a conductive workpiece. In the EDM process, a tool electrode is moved close to the workpiece and an electric spark is generated via a dielectric fluid between them, vaporizing a small amount of material. This process is repeated many times to gradually shape the workpiece. EDM can machine very hard materials and complex shapes without causing mechanical stress to the workpiece. Common applications include drilling micro holes, cutting intricate profiles, and machining hardened steel dies and molds.
The document provides information on Electrical Discharge Machining (EDM). EDM is a manufacturing process where electrical discharges are used to erode material from a workpiece to achieve a desired shape. In EDM, a series of sparks erode material by rapidly recurring electrical discharges between two electrodes separated by a dielectric liquid and subject to an electric voltage. One electrode is the tool that shapes the workpiece. Material removal occurs through thermal melting and vaporization caused by the extreme heat of electrical sparks between the electrodes.
Electrical Discharge Machining (EDM) is a manufacturing process where electrical discharges are used to erode material from a workpiece to achieve a desired shape. In EDM, a potential difference is applied between an electrode tool and the workpiece, which are separated by a dielectric liquid. This causes electric sparks to form that melt and vaporize small amounts of material from both the tool and workpiece. Kerosene or deionized water is typically used as the dielectric liquid to facilitate flushing of debris and prevent oxidation during the process.
Electrical Discharge Machining (EDM) is a manufacturing process where electrical discharges are used to erode material from a workpiece to achieve a desired shape. In EDM, a series of electrical sparks are generated between two electrodes submerged in a dielectric liquid and subject to an electric voltage. This causes material to be removed from both electrodes through localized melting and vaporization due to the extreme heat of the sparks. EDM can be used to machine hard metals and intricate shapes that would be difficult to machine through conventional methods.
The document discusses Electrical Discharge Machining (EDM). EDM is a manufacturing process where a desired shape is obtained by removing material from a workpiece using electrical discharges between two electrodes separated by a dielectric liquid. As the distance between the electrodes is reduced, current flows due to dielectric breakdown causing material removal from both electrodes. EDM was invented in the 1940s and has since improved, increasing machining speeds and reducing costs. EDM can machine hard metals and intricate shapes without needing to soften the material. The main components of an EDM system are the power supply, dielectric medium, workpiece and tool electrodes, and servo control unit. Material is removed through the formation and collapse of plasma channels between the electrodes during
Here you are watching PowerPoint Presentation of EDM (Electrical Machining Process). It is a kind of unconventional machining process.Thanks for watching.
Electro Discharge Machining (EDM) is a non-traditional machining process that uses electrical sparks to remove material. In EDM, an electric spark is generated between an electrode tool and conductive workpiece submerged in a dielectric fluid. This spark removes microscopic amounts of material through thermal erosion. EDM can machine hard metals and complex shapes. It produces a recast layer on the workpiece surface with altered properties that may require post-machining treatment. Common applications of EDM include die and mold making.
Full details of Electroc discharge machine ,Ultrasonic machining, Electro Che...ManojSingh376471
This document provides information on three non-traditional machining processes: electric discharge machining (EDM), ultrasonic machining (USM), and electrochemical machining (ECM). EDM uses electric sparks to erode material away from a workpiece. USM employs abrasive particles and ultrasonic tool vibration to machine brittle materials. ECM removes metal from a workpiece using electrolysis with the workpiece as the anode. Key aspects of each process like operating principles, applications, and important process parameters are described. Diagrams illustrate EDM working, wire EDM, USM setup, and ECM principles.
This document discusses electric discharge machining (EDM). It describes the working principle of EDM, which uses electric sparks to remove small amounts of material from conductive workpieces and tools. The key components of an EDM system are described, including the power supply, dielectric system, electrodes (tool and workpiece), and servo system. The document explains how EDM uses an electric spark to melt and vaporize small amounts of material from both electrodes. It also discusses factors that influence the EDM process such as electrode material, dielectric fluid, flushing, and process parameters.
Electric discharge machining (EDM) involves removing material from a workpiece using electrical discharges between two electrodes separated by a dielectric liquid. It was invented in the 1940s by Russian physicists and can machine hard metals and intricate shapes that other methods cannot. The document discusses the history, working principle, material removal mechanism, advantages, and applications of EDM. It also covers technical parameters like electrode materials, dielectric fluids, and process variables that influence the material removal rate.
Electrical discharge machining (EDM) is a machining process that uses electrical discharges to erode material from a conductive workpiece. It was pioneered in the 1940s and uses a tool and workpiece submerged in a dielectric fluid. An electric current is applied between the tool and workpiece, causing electric sparks that melt and vaporize small amounts of material. Key parameters that affect the process include discharge voltage, current, pulse duration and polarity. EDM allows machining very hard materials and complex shapes regardless of hardness, and provides a high-quality surface finish.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
This document discusses electrical discharge machining (EDM), including its components, working principle, characteristics, advantages, disadvantages, and applications. EDM uses electrical discharges between an electrode tool and conductive workpiece to remove material. Key components include a power supply, dielectric medium like kerosene, and servo control unit. Material is removed through rapid sparking caused by a voltage difference across a small gap filled with dielectric fluid. EDM can machine hard metals and intricate shapes without heat treating.
Electrical Discharge Machine is an advanced machining method which removes metal by a series of recurring electrical discharges betweenn an electrode and a conductive workpiece, submerged in a dielectric fluid.
Introduction to Electric Discharge MachiningDignesh Parmar
The document provides information about electric discharge machining (EDM). It discusses the history of EDM, which began in the 18th century with observations of erosion from electric discharge. EDM was developed in the 1940s and commercialized in the 1950s. The document describes the basic working principles of EDM, including how material is removed through electric sparks between electrodes. It also covers aspects like power generators, material removal rates, surface roughness, electrode materials and movement.
This document provides an overview of electro discharge machining (EDM). It discusses the working principle of EDM, which involves using electric sparks to erode metal to the desired shape. The key components of EDM are described, including the power generator, dielectric fluid, electrode tool, and fixture. Characteristics of EDM like its ability to machine hard materials regardless of strength are summarized. Advantages include machining complex shapes and tight tolerances, while disadvantages include slow removal rates and electrode wear. Applications of EDM mentioned are drilling micro-holes, cutting threads, and machining hardened alloys.
Experimental Investigation of Electrode Wear in Die-Sinking EDM on Different ...IJMER
This document summarizes an experimental investigation of electrode wear in die-sinking electrical discharge machining (EDM) using different pulse-on and pulse-off times. The study examined electrode wear in cylindrical copper electrodes machining die-steel workpieces. Electrode wear was measured by weight loss and length reduction of the copper electrodes under different pulse-on, pulse-off times and constant current. The results showed that electrode wear decreased with increasing pulse-on and pulse-off times, and was minimized at a pulse-on time of 200 microseconds and pulse-off time of 30 microseconds at 12 amperes of current. The study concluded that optimizing pulse-on, pulse-off times can reduce electrode wear and improve the
Electro Discharge Machining
Introduction
Process
Process Parameters
Dielectric
Advantages of EDM
APPLICATIONS
Power generator
Wire EDM
ELECTRIC DISCHARGE GRINDING (EDG)
Electrical discharge machining (EDM) is a thermal machining process that uses electrical sparks to erode materials. EDM can machine hard metals and intricate shapes that would be difficult to produce with other methods. In EDM, an electrode is separated from the workpiece by a small gap filled with dielectric fluid. A series of electrical discharges passes between the electrode and workpiece, melting and vaporizing small amounts of material. This repetitive process creates a replica of the electrode shape in the workpiece. EDM can machine hard metals like tool steels and carbides with good accuracy and surface finish.
Seminar report on electric discharge machineAnkit Amlan
This document provides a seminar report on electric discharge machining (EDM) by Ankit Amlan, a 7th semester mechanical engineering student at VSSUT, Burla. The report details EDM work done by Amlan at Hindustan Aeronautics Limited in Sunabeda. It covers the history of EDM, working principles, material removal mechanisms, types of EDM including sinker and wire-cut, applications, and advantages/disadvantages. Pictures and diagrams are included to illustrate EDM systems and processes.
Electron beam machining (EBM) uses a focused electron beam within a vacuum environment to drill small, high-aspect-ratio holes in materials. The electron beam is generated by heating a cathode filament to produce electrons, which are accelerated and focused onto the workpiece. Upon impact, the kinetic energy of the electrons is converted to heat, instantly melting and vaporizing the material. Multiple pulses are required to drill deeper holes. While EBM can precisely machine fragile materials with minimal heat impact, it has high equipment costs and requires regular maintenance of the vacuum systems.
Wire electrical discharge machining uses a thin electrically charged wire as an electrode to cut conductive materials precisely through controlled electrical sparks. During the process, hundreds of thousands of sparks per second melt and vaporize tiny amounts of material from both the wire and workpiece. The wire is continuously advanced and small debris is flushed away by a dielectric fluid, allowing complex shapes to be cut without physical contact between the wire and workpiece. This results in parts with an excellent surface finish and no burrs.
Wire electrical discharge machining (EDM) is a non-traditional machining process that uses electricity to cut any conductive material precisely and accurately with a thin, electrically charged copper or brass wire as an electrode. During the wire EDM process, the wire carries one side of an electrical charge and the workpiece carries the other side of the charge. When the wire gets close to the part, the attraction of electrical charges creates a controlled spark, melting and vaporizing microscopic particles of material. Plasma arc cutting (PAC) uses a plasma torch to direct a high-velocity jet of hot plasma from an ionized gas to cut electrically conductive materials. PAC systems operate on either a non-transferred arc mode or transferred arc
Wire electrical discharge machining uses a thin electrically charged wire as an electrode to cut conductive materials precisely through controlled electrical sparks. During the process, hundreds of thousands of sparks per second melt and vaporize tiny amounts of material from both the wire and workpiece. The wire is continuously advanced and small debris is flushed away by a dielectric fluid, allowing complex shapes to be cut without physical contact between the wire and workpiece. This results in parts with an excellent surface finish and no burrs.
Wire electrical discharge machining (EDM) is a non-traditional machining process that uses electricity to cut any conductive material precisely and accurately with a thin, electrically charged copper or brass wire as an electrode. During the wire EDM process, the wire carries one side of an electrical charge and the workpiece carries the other side of the charge. When the wire gets close to the part, the attraction of electrical charges creates a controlled spark, melting and vaporizing microscopic particles of material. Plasma arc cutting (PAC) uses a plasma torch to direct a high-velocity jet of hot plasma from an ionized gas to cut electrically conductive materials. PAC systems operate on either a non-transferred arc mode or transferred arc
Wire electrical discharge machining uses a thin electrically charged wire as an electrode to cut conductive materials precisely through controlled electrical sparks. During the process, hundreds of thousands of sparks per second melt and vaporize tiny amounts of material from both the wire and workpiece. The wire is continuously advanced and small debris is flushed away by a dielectric fluid, allowing complex shapes to be cut without physical contact between the wire and workpiece. This results in parts with an excellent surface finish and no burrs.
Current Advanced Research Development of Electric Discharge Machining (EDM): ...sushil Choudhary
Electrical discharge machining (EDM) process is one of the most commonly used nonconventional
precise material removal processes. Electrical discharge machining (EDM) is a process for
shaping hard metals and forming deep complex shaped holes by arc erosion in all kinds of electroconductive
materials. Erosion pulse discharge occurs in a small gap between the work piece and the
electrode. This removes the unwanted material from the parent metal through melting and vaporizing in
presence of dielectric fluid. In recent years, EDM researchers have explored a number of ways to improve
EDM Process parameters such as Electrical parameters, Non-Electrical Parameters, tool Electrode based
parameters & Powder based parameters. This new research shares the same objectives of achieving more
efficient metal removal rate reduction in tool wear and improved surface quality. This paper reviews the
research work carried out from the inception to the development of die-sinking EDM, Water in EDM, dry
EDM, and Powder mixed electric Discharge Machining. Within the past decade. & also briefly describing the Current Research technique Trend in EDM, future EDM research direction.
Electron beam welding is a fusion welding process that uses a beam of high-velocity electrons to melt and join materials. It works by accelerating free electrons in a vacuum and focusing them via electric and magnetic fields to produce an intense heat source. The process requires a power supply, electron gun, anode, magnetic lenses, work holding devices, and a vacuum chamber. It is capable of welding a variety of materials with advantages like narrow seams, low heat input, and the ability to weld thin and thick plates.
The document describes the parts and functions of a lathe machine. It discusses the bed, headstock, tailstock, carriage, feed mechanism, and other major components. The headstock holds and rotates the workpiece while the carriage supports the cutting tool and allows it to move longitudinally. Common lathe operations like turning, facing, tapering and chamfering are also summarized. Safety practices and proper use of lathes, tool holders and accessories are emphasized.
The excess free cash flow model, excess operating cash flow model, and excess earnings model are all valuation methods that are equivalent to discounted cash flow (DCF) valuation under consistent implementation. They discount excess accounting earnings or residual income instead of excess free cash flows. The key difference between the models is how changes in working capital, accruals, and capital expenditures are treated. Specifically, the excess earnings model can be restated as the DCF model plus components related to changes in investments and accruals.
This document discusses electric discharge machining (EDM). It describes the working principle of EDM, which uses electric sparks to remove small amounts of material from conductive workpieces and tools. The key components of an EDM system are described, including the power supply, dielectric system, electrodes (tool and workpiece), and servo system. The document explains how EDM uses an electric spark to melt and vaporize small amounts of material from both electrodes. It also discusses factors that influence the EDM process such as electrode material, dielectric fluid, flushing, and process parameters.
Electric discharge machining (EDM) involves removing material from a workpiece using electrical discharges between two electrodes separated by a dielectric liquid. It was invented in the 1940s by Russian physicists and can machine hard metals and intricate shapes that other methods cannot. The document discusses the history, working principle, material removal mechanism, advantages, and applications of EDM. It also covers technical parameters like electrode materials, dielectric fluids, and process variables that influence the material removal rate.
Electrical discharge machining (EDM) is a machining process that uses electrical discharges to erode material from a conductive workpiece. It was pioneered in the 1940s and uses a tool and workpiece submerged in a dielectric fluid. An electric current is applied between the tool and workpiece, causing electric sparks that melt and vaporize small amounts of material. Key parameters that affect the process include discharge voltage, current, pulse duration and polarity. EDM allows machining very hard materials and complex shapes regardless of hardness, and provides a high-quality surface finish.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
This document discusses electrical discharge machining (EDM), including its components, working principle, characteristics, advantages, disadvantages, and applications. EDM uses electrical discharges between an electrode tool and conductive workpiece to remove material. Key components include a power supply, dielectric medium like kerosene, and servo control unit. Material is removed through rapid sparking caused by a voltage difference across a small gap filled with dielectric fluid. EDM can machine hard metals and intricate shapes without heat treating.
Electrical Discharge Machine is an advanced machining method which removes metal by a series of recurring electrical discharges betweenn an electrode and a conductive workpiece, submerged in a dielectric fluid.
Introduction to Electric Discharge MachiningDignesh Parmar
The document provides information about electric discharge machining (EDM). It discusses the history of EDM, which began in the 18th century with observations of erosion from electric discharge. EDM was developed in the 1940s and commercialized in the 1950s. The document describes the basic working principles of EDM, including how material is removed through electric sparks between electrodes. It also covers aspects like power generators, material removal rates, surface roughness, electrode materials and movement.
This document provides an overview of electro discharge machining (EDM). It discusses the working principle of EDM, which involves using electric sparks to erode metal to the desired shape. The key components of EDM are described, including the power generator, dielectric fluid, electrode tool, and fixture. Characteristics of EDM like its ability to machine hard materials regardless of strength are summarized. Advantages include machining complex shapes and tight tolerances, while disadvantages include slow removal rates and electrode wear. Applications of EDM mentioned are drilling micro-holes, cutting threads, and machining hardened alloys.
Experimental Investigation of Electrode Wear in Die-Sinking EDM on Different ...IJMER
This document summarizes an experimental investigation of electrode wear in die-sinking electrical discharge machining (EDM) using different pulse-on and pulse-off times. The study examined electrode wear in cylindrical copper electrodes machining die-steel workpieces. Electrode wear was measured by weight loss and length reduction of the copper electrodes under different pulse-on, pulse-off times and constant current. The results showed that electrode wear decreased with increasing pulse-on and pulse-off times, and was minimized at a pulse-on time of 200 microseconds and pulse-off time of 30 microseconds at 12 amperes of current. The study concluded that optimizing pulse-on, pulse-off times can reduce electrode wear and improve the
Electro Discharge Machining
Introduction
Process
Process Parameters
Dielectric
Advantages of EDM
APPLICATIONS
Power generator
Wire EDM
ELECTRIC DISCHARGE GRINDING (EDG)
Electrical discharge machining (EDM) is a thermal machining process that uses electrical sparks to erode materials. EDM can machine hard metals and intricate shapes that would be difficult to produce with other methods. In EDM, an electrode is separated from the workpiece by a small gap filled with dielectric fluid. A series of electrical discharges passes between the electrode and workpiece, melting and vaporizing small amounts of material. This repetitive process creates a replica of the electrode shape in the workpiece. EDM can machine hard metals like tool steels and carbides with good accuracy and surface finish.
Seminar report on electric discharge machineAnkit Amlan
This document provides a seminar report on electric discharge machining (EDM) by Ankit Amlan, a 7th semester mechanical engineering student at VSSUT, Burla. The report details EDM work done by Amlan at Hindustan Aeronautics Limited in Sunabeda. It covers the history of EDM, working principles, material removal mechanisms, types of EDM including sinker and wire-cut, applications, and advantages/disadvantages. Pictures and diagrams are included to illustrate EDM systems and processes.
Electron beam machining (EBM) uses a focused electron beam within a vacuum environment to drill small, high-aspect-ratio holes in materials. The electron beam is generated by heating a cathode filament to produce electrons, which are accelerated and focused onto the workpiece. Upon impact, the kinetic energy of the electrons is converted to heat, instantly melting and vaporizing the material. Multiple pulses are required to drill deeper holes. While EBM can precisely machine fragile materials with minimal heat impact, it has high equipment costs and requires regular maintenance of the vacuum systems.
Wire electrical discharge machining uses a thin electrically charged wire as an electrode to cut conductive materials precisely through controlled electrical sparks. During the process, hundreds of thousands of sparks per second melt and vaporize tiny amounts of material from both the wire and workpiece. The wire is continuously advanced and small debris is flushed away by a dielectric fluid, allowing complex shapes to be cut without physical contact between the wire and workpiece. This results in parts with an excellent surface finish and no burrs.
Wire electrical discharge machining (EDM) is a non-traditional machining process that uses electricity to cut any conductive material precisely and accurately with a thin, electrically charged copper or brass wire as an electrode. During the wire EDM process, the wire carries one side of an electrical charge and the workpiece carries the other side of the charge. When the wire gets close to the part, the attraction of electrical charges creates a controlled spark, melting and vaporizing microscopic particles of material. Plasma arc cutting (PAC) uses a plasma torch to direct a high-velocity jet of hot plasma from an ionized gas to cut electrically conductive materials. PAC systems operate on either a non-transferred arc mode or transferred arc
Wire electrical discharge machining uses a thin electrically charged wire as an electrode to cut conductive materials precisely through controlled electrical sparks. During the process, hundreds of thousands of sparks per second melt and vaporize tiny amounts of material from both the wire and workpiece. The wire is continuously advanced and small debris is flushed away by a dielectric fluid, allowing complex shapes to be cut without physical contact between the wire and workpiece. This results in parts with an excellent surface finish and no burrs.
Wire electrical discharge machining (EDM) is a non-traditional machining process that uses electricity to cut any conductive material precisely and accurately with a thin, electrically charged copper or brass wire as an electrode. During the wire EDM process, the wire carries one side of an electrical charge and the workpiece carries the other side of the charge. When the wire gets close to the part, the attraction of electrical charges creates a controlled spark, melting and vaporizing microscopic particles of material. Plasma arc cutting (PAC) uses a plasma torch to direct a high-velocity jet of hot plasma from an ionized gas to cut electrically conductive materials. PAC systems operate on either a non-transferred arc mode or transferred arc
Wire electrical discharge machining uses a thin electrically charged wire as an electrode to cut conductive materials precisely through controlled electrical sparks. During the process, hundreds of thousands of sparks per second melt and vaporize tiny amounts of material from both the wire and workpiece. The wire is continuously advanced and small debris is flushed away by a dielectric fluid, allowing complex shapes to be cut without physical contact between the wire and workpiece. This results in parts with an excellent surface finish and no burrs.
Current Advanced Research Development of Electric Discharge Machining (EDM): ...sushil Choudhary
Electrical discharge machining (EDM) process is one of the most commonly used nonconventional
precise material removal processes. Electrical discharge machining (EDM) is a process for
shaping hard metals and forming deep complex shaped holes by arc erosion in all kinds of electroconductive
materials. Erosion pulse discharge occurs in a small gap between the work piece and the
electrode. This removes the unwanted material from the parent metal through melting and vaporizing in
presence of dielectric fluid. In recent years, EDM researchers have explored a number of ways to improve
EDM Process parameters such as Electrical parameters, Non-Electrical Parameters, tool Electrode based
parameters & Powder based parameters. This new research shares the same objectives of achieving more
efficient metal removal rate reduction in tool wear and improved surface quality. This paper reviews the
research work carried out from the inception to the development of die-sinking EDM, Water in EDM, dry
EDM, and Powder mixed electric Discharge Machining. Within the past decade. & also briefly describing the Current Research technique Trend in EDM, future EDM research direction.
Electron beam welding is a fusion welding process that uses a beam of high-velocity electrons to melt and join materials. It works by accelerating free electrons in a vacuum and focusing them via electric and magnetic fields to produce an intense heat source. The process requires a power supply, electron gun, anode, magnetic lenses, work holding devices, and a vacuum chamber. It is capable of welding a variety of materials with advantages like narrow seams, low heat input, and the ability to weld thin and thick plates.
Similar to ELECTRO_DISCHARGE_MACHINING_EDM.pptx (20)
The document describes the parts and functions of a lathe machine. It discusses the bed, headstock, tailstock, carriage, feed mechanism, and other major components. The headstock holds and rotates the workpiece while the carriage supports the cutting tool and allows it to move longitudinally. Common lathe operations like turning, facing, tapering and chamfering are also summarized. Safety practices and proper use of lathes, tool holders and accessories are emphasized.
The excess free cash flow model, excess operating cash flow model, and excess earnings model are all valuation methods that are equivalent to discounted cash flow (DCF) valuation under consistent implementation. They discount excess accounting earnings or residual income instead of excess free cash flows. The key difference between the models is how changes in working capital, accruals, and capital expenditures are treated. Specifically, the excess earnings model can be restated as the DCF model plus components related to changes in investments and accruals.
This document discusses decision analysis and different methods for making decisions under uncertainty. It introduces decision analysis concepts including alternative actions, states of nature, and outcomes. It then covers three decision making conditions: certainty, ignorance, and risk. Under risk, it discusses expected return/value and how to calculate it using probabilities and payoffs. It also introduces the concepts of maximax, maximin, expected value of perfect information, and utility functions to incorporate risk attitudes into decisions.
El documento presenta la capacitación de febrero 2016 para el personal de Innova Schools en Lima y provincias. Se capacitará a los profesores en grupos según su especialidad y nivel de experiencia, utilizando la modalidad grupo. Algunos profesores de provincia vendrán a Lima mientras que otros se capacitarán en su sede. Se detallan las fechas, lugares y procedimientos para la capacitación.
O documento descreve as principais fontes escritas do judaísmo rabínico, incluindo a Tanakh, os Targumim, os Midrashim e a Mishná. A tradição oral é central para o judaísmo rabínico e a Mishná foi compilada pelo Rabi Judá HaNassi para codificar a lei oral. O documento também lista importantes comentaristas como Rashi e Maimônides.
This document discusses cybercrime, including definitions, instruments, objectives, and legislation. It defines cybercrime as the use of computers or technology to commit illegal acts. Cybercrime can target computers themselves through malware or use computers as an intermediary to commit property, economic, personal, or political crimes. The document outlines international cooperation efforts and legal instruments addressing cybercrime, such as the Council of Europe's Convention on Cybercrime. The International Telecommunication Union works to develop model cybercrime laws and facilitate capacity building and international cooperation around combating cybercrime. Creating universally applicable international cybercrime legislation faces challenges due to the nature of cybercrime and political tensions between countries.
NeuroAIDS refers to the neurological complications caused by HIV infection in the central and peripheral nervous systems. It can be caused primarily by the virus or secondarily by opportunistic infections. The virus does not directly infect neurons but damages them indirectly by infecting microglia, macrophages and astrocytes in the brain. This leads to clinical syndromes involving cognitive, motor and behavioral dysfunction. Common conditions include AIDS dementia, peripheral neuropathy, vacuolar myelopathy and primary CNS lymphoma. Diagnosis involves brain imaging, spinal fluid analysis and biopsy. Treatment focuses on ART, managing symptoms, and treating any underlying opportunistic infections.
Blitz was a Portuguese music magazine established in 1984 that aligned itself with emerging underground music scenes in opposition to the dominant record industry. The magazine's journalists saw themselves as "militant" in their promotion of new artists and tastes over mainstream commercial music. Through its writing, Blitz advocated an "ideology of difference" that valued creativity, innovation, and authenticity over imitation, conservatism, and music made only for mass popularity. This ideological stance positioned the magazine and its journalism against the mainstream Portuguese music industry and in support of independent labels, radio shows, retailers, and other media that shared its focus on new and different artists.
El documento resume la situación demográfica y económica del Perú. La población peruana ha crecido constantemente entre 2001 y 2015. Lima es la región más poblada y ha aumentado su población en más de 7 millones de personas durante este período. La economía peruana ha experimentado un fuerte crecimiento en los últimos años, con tasas de crecimiento del PIB superiores al 6% en 2012, impulsada por la inversión privada y pública. Sin embargo, existen desafíos para garantizar un crecimiento sostenible a larg
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Hatshepsut was the fifth pharaoh of the Eighteenth Dynasty in Egypt. She became regent after the death of Thutmose II until Thutmose III came of age, and they ruled jointly for some time. Hatshepsut challenged gender norms by taking on the role and image of a male pharaoh. She initiated extensive building projects and expanded trade networks during her prosperous reign, establishing herself as a powerful ruler through relationship with the god Amen and portrayals of her divine authority.
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Worksheet for a Merchandising Business.pptJiaJunWang17
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The revolutions in Tunisia and Egypt shared some similarities but ultimately led to different outcomes. Both overthrew long-standing authoritarian regimes in 2011 but Tunisia has transitioned more successfully to democracy while Egypt has reverted to authoritarianism. Key factors in Tunisia's success include stronger civil society, political compromise across ideological lines, and support from international actors for democratic reforms. Egypt has struggled due to political polarization, an influential military with authoritarian tendencies, and a lack of consensus on democratic values and institutions.
Use PyCharm for remote debugging of WSL on a Windo cf5c162d672e4e58b4dde5d797...shadow0702a
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2. INTRODUCTION
Electro Discharge Machining (EDM) is an electro-thermal non-
traditional machining process, where electrical energy is used to
generate electrical spark and material removal mainly occurs due to
thermal energy of the spark.
EDM is mainly used to machine difficult-to-machine materials and high
strength temperature resistant alloys.
EDM can be used to machine difficult geometries in small batches or
even on job-shop basis.
Work material to be machined by EDM has to be electrically
conductive. 2
3. MAJOR COMPONENTS OF EDM
The main components of EDM are
Electric power supply
Work piece & tool
Dielectric medium
Servo control unit.
3
4. WORKING
In EDM, a potential difference is applied between the tool and work piece.
Both the tool and the work material are to be conductors of electricity.
The tool and the work material are immersed in a dielectric medium.
Dielectric Medium-kerosene or deionised water.
Gap is maintained between the tool and the work piece.
Depending upon the applied potential difference and the gap between the
tool and work piece, an electric field would be established.
4
5. WORKING (CONT..,)
Tool is connected to the negative terminal of the generator and the work
piece is connected to positive terminal.
As the electric field is established between the tool and the job, the free
electrons on the tool are subjected to electrostatic forces
“cold emission”- the work function or the bonding energy of the electrons
is less, electrons would be emitted from the tool (assuming it to be
connected to the negative terminal).
Such emission of electrons are called or termed as cold emission.
5
7. WORKING (CONT..,)
The “cold emitted” electrons are then accelerated towards the job
through the dielectric medium, as they gain velocity and energy, and
start moving towards the job, there would be collisions between the
electrons and dielectric molecules. Such collision may result in
ionization of the dielectric molecule.
As the electrons get accelerated, more positive ions and electrons
would get generated due to collisions.
This cyclic process would increase the concentration of electrons
and ions in the dielectric medium between the tool and the job at the
spark gap. 7
8. WORKING (CONT..,)
The concentration would be so high that the matter existing in that
channel could be characterized as “plasma”.
8
9. WORKING (CONT..,)
The electrical resistance of such plasma channel would be very less.
Thus all of a sudden, a large number of electrons will flow from
tool to job and ions from job to tool.
This is called avalanche motion of electrons.
Such movement of electrons and ions can be visually seen as a
spark.
Thus the electrical energy is dissipated as the thermal energy of the
spark.
The high speed electrons then impinge on the job and ions onthe
tool.
The kinetic energy of the electrons and ions on impact with the
surface of the job and tool respectively would be converted into
thermal energy or heat flux.
9
10. WORKING (CONT..,)
Such intense localized heat flux leads to extreme instantaneous
confined rise in temperature which would be in excess of 10,000oC.
Such localized extreme rise in temperature leads to material removal.
Material removal occurs due to instant vaporization of the material as
well as due to melting.
The molten metal is not removed completely but only partially.
As the potential difference is withdrawn, the plasma channel is no
longer sustained. As the plasma channel collapse, it generates pressure
or shock waves, which evacuates the molten material forming a crater
of removed material around the site of the spark. 10
11. WORKING (CONT..,)
Upon withdrawal of potential difference, plasma channel collapses.
This ultimately creates compression shock waves on the electrode surface.
Particularly at high spots on work piece surface, which are closest to the
tool.
This evacuates molten material and forms a crater around the site of the
spark.
The whole sequence of operation occurs within a few microseconds.
11
12. SUMMARY
The material removal in EDM mainly occurs due to formation of shock waves
as the plasma channel collapse owing to discontinuation of applied potential
difference
Generally the work piece is made positive and the tool negative.
Hence, the electrons strike the job leading to crater formation due to high
temperature and melting and material removal.
Similarly, the positive ions impinge on the tool leading to tool wear.
The generator is used to apply voltage pulses between the tool and job.
A constant voltage is not applied. Only sparking is desired rather thanarcing.
Arcing leads to localized material removal at a particular point whereas sparks
get distributed all over the tool surface leading to uniform material removal. 12
13. ELECTRODE
Electrode material should be such that it would not undergomuch
tool wear when it is impinged by positive ions.
Thus the localized temperature rise has to be less by properly
choosing its properties or even when temperature increases, there
would be less melting.
High electrical conductivity – electrons are cold emitted more easily
and there is less bulk electrical heating
High thermal conductivity – for the same heat load, the local
temperature rise would be less due to faster heat conducted to the
bulk of the tool and thus less tool wear 13
14. 14
Higher density – for the same heat load and same tool wear by weight there
would be less volume removal or tool wear and thus less dimensional loss
or inaccuracy .
High melting point – high melting point leads to less tool wear due to less
tool material melting for the same heat load
Easy manufacturability
Cost – cheap
Recommended Electrode materials:
Graphite
Electrolytic oxygen free copper
Tellurium copper – 99% Cu + 0.5% tellurium
Brass
15. DIELECTRIC
Material removal mainly occurs due to thermal evaporation and melting.
As thermal processing is required to be carried out in absence of oxygen so that
the process can be controlled and oxidation avoided.
Oxidation often leads to poor surface conductivity (electrical) of the workpiece
hindering further machining .
Dielectric fluid should provide an oxygen free machining environment.
Further it should have enough strong dielectric resistance so that it does not
breakdown electrically too easily.
But at the same time, it should ionize when electrons collide with its molecule.
Moreover, during sparking it should be thermally resistant as well.
Generally kerosene and deionised water is used as dielectric fluid in EDM.
15
16. DIELECTRIC
Tap water cannot be used as it ionizes too early and thus breakdown due to
presence of salts as impurities occur.
Dielectric medium is generally flushed around the spark zone.
It is also applied through the tool to achieve efficient removal of molten
material.
Three important functions of a dielectric medium in EDM:
1. Insulates the gap between the tool and work, thus preventing a spark to
form until the gap voltage are correct.
2. Cools the electrode, workpiece and solidifies the molten metal particles.
3. Flushes the metal particles out of the working gap to maintain ideal
cutting conditions, increase metal removal rate. 16
17. DIELECTRIC
It must be filtered and circulated at constant pressure
The main requirements of the EDM dielectric fluids are adequate
viscosity, high flash point, good oxidation stability, minimum odor,
low cost, and good electrical discharge efficiency.
For most EDM operations kerosene is used with certain additives that
prevent gas bubbles and de-odoring.
Silicon fluids and a mixture of these fluids with petroleum oils have
given excellent results.
Other dielectric fluids with a varying degree of success include
aqueous solutions of ethylene glycol, water in emulsions, and distilled
water.
17
18. POWER GENERATOR
Different power generators are used in EDM and some are
listed below
Resistance-capacitance type (RC type) Relaxation generator
Rotary impulse type generator
Electronic pulse generator
Hybrid EDM generator
18
20. RC TYPE RELAXATION GENERATOR
The capacitor is charged from a DC source.
As long as the voltage in the capacitor is not reaching the
breakdown voltage of the dielectric medium under the prevailing
machining condition, capacitor would continue to charge.
Once the breakdown voltage is reached the capacitor would start
discharging and a spark would be established between the tool and
workpiece leading to machining.
Such discharging would continue as long as the spark can be
sustained. Once the voltage becomes too low to sustain the spark,
the charging of the capacitor would continue. 20
21. 21
Thus at any instant charging current, ic can be given as:
where,
Ic = charging current
Id =discharging current
Vo= open circuit voltage
Rc= charging resistance
C = capacitance
Vc= instantaneous capacitor voltage during
charging
The discharging or the machining current Id is given by
22. 22
For maximum power dissipation in RC type EDM generator
Vc
* = 0.716Vo.
The discharging time or machining time or on time can be
expressed as
26. The waveform is characterized by the
o The open circuit voltage - Vo
o The working voltage -Vw
o The maximum current - Io
oThe pulse on time – the duration for which the voltage pulse is
applied - ton
o The pulse off time - toff
o The gap between the workpiece and the tool – spark gap - δ
o The polarity – straight polarity – tool (-ve)
o The dielectric medium
o External flushing through the spark gap.
26
28. PROCESS PARAMETERS (CONTD..,)
ngle spark is
Material removal rate:
28
material removal in a single spark can be expressed as
T
ool
Spark
the energy content of a si
Crater
30. EDM – CHARACTERISTICS
Can be used to machine any work material if it is electrically
conductive.
Capacitor discharge is between 50 and 380 V
Dielectric slurry is forced through this gap at a pressure of 2
kgf/cm2 or lesser.
A gap, known as SPARK GAP in the range, from 0.005 mm to
0.05 mm is maintained between the work piece and the tool.
The current density in the discharge of the channel is of the order
of 10000 A/cm2 and power density is nearly 500 MW/cm2.
MRR depends on thermal properties (job) rather than its strength,
hardness etc.
The volume of the material removed per spark discharge is
typically in the range of (1/1,000,000) to (1/10,000) mm3.
30
31. EDM – CHARACTERISTICS (CONTD..,)
In EDM, geometry of tool - positive impression of hole or
geometric feature.
Tool wear once again depends on the thermal properties of tool
material.
Local temperature rise is rather high, but there is not enough heat
diffusion (very small pulse on time) and thus HAZ is limited to 2 –
4 μm.
Rapid heating and cooling leads to surface hardening which may
be desirable in some applications.
Tolerance value of + 0.05 mm could be easily achieved by EDM.
Best surface finish that can be economically achieved on steel is
0.40 m
31
32. APPLICATIONS
Drilling of micro-holes, thread cutting, helical profilemilling,
rotary forming, and curved hole drilling.
Delicate work piece like copper parts can be produced by EDM.
Can be applied to all electrically conducting metals and alloys
irrespective of their melting points, hardness, toughness, or
brittleness.
Other applications: deep, small-dia holes using tungsten wire as
tool, narrow slots, cooling holes in super alloy turbine blades,and
various intricate shapes.
EDM can be economically employed for extremely hardened work
piece.
Since there is no mechanical stress present (no physical contact),
fragile and slender work places can be machined without distortion.
Hard and corrosion resistant surfaces, essentially needed fordie
making, can be developed
32
33. ADVANTAGES
Some of the advantages of EDM include machining of:
Complex shapes that would otherwise be difficult to producewith
conventional cutting tools.
Extremely hard material to very close tolerances.
Very small work pieces where conventional cutting tools may
damage the part from excess cutting tool pressure.
There is no direct contact between tool and work piece. Therefore
delicate sections and weak materials can be machined without any
distortion.
A good surface finish can beobtained. 33
34. DISADVANTAGES
Some of the disadvantages of EDM include:
The slow rate of material removal.
For economic production, the surface finish specified should notbe
too fine.
The additional time and cost used for creating electrodesfor
ram/sinker EDM.
Reproducing sharp corners on the workpiece is difficult dueto
electrode wear.
Power consumption is high.
"Overcut" is formed.
Excessive tool wear occurs during machining.
Electrically non-conductive materials can be machined only with
specific set-up of the process 34