scholarly journals Comparative Analysis of Dry-EDM and Conventional EDM in machining of Hastelloy

2021 ◽  
Vol 12 (3) ◽  
pp. 3538-3543
Author(s):  
Apurva A Kulkarni Et.al
Keyword(s):  
High Velocity ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
White Layer ◽  
Dielectric Medium ◽  
Work Piece ◽  
Tool Electrode ◽  
Dry Edm ◽  
Discharge Gap ◽  
Edm Process

Dry EDM may be a modification of the traditional electrical discharge machining (EDM) process during which the liquid dielectric is replaced by a gaseous medium. High velocity gas is supplied through it into the discharge gap. The flow of high velocity gas into the gap facilitates removal of debris and prevents excessive heating of the tool and work piece at the discharge spots. it's now known that aside from being an environment–friendly process, other advantages of the dry EDM process are low tool wear, lower discharge gap, lower residual stresses, smaller white layer and smaller heat affected zone.[1] Keeping literature review into consideration, during this research, an effort has been made by selecting compressed gas as a dielectric medium, with Hastelloy as a work piece material and copper as a tool electrode. Conventional experiments were also performed. Experiments are performed using Taguchi DoE orthogonal array to watch and analysis the consequences of various process parameters to optimize the response variables like material removal rate (MRR) and gear wear rate (TWR).

Performance Evaluation of Dry EDMed Aluminium Alloy

2015 ◽  
Author(s):  
M. Pradeep Kumar ◽  
N. Pragadish
Keyword(s):  
Surface Roughness ◽  
Aluminium Alloy ◽  
Removal Rate ◽  
Research Work ◽  
Work Piece ◽  
Tool Electrode ◽  
Dry Edm ◽  
Input Parameters ◽  
Pulse On Time ◽  
Edm Process

In this research work, experiments were conducted using Electrical Discharge Machining (EDM) in dry and conventional mode, and the results were compared and analyzed. LM13 Aluminium alloy is used as the workpiece and pure cylindrical copper rod is used as the tool electrode. Since the machining was difficult in dry EDM, some modifications were made in the existing tool design to conduct the experiments in dry EDM. The experiments were designed using Taguchi’s L27 orthogonal array. Discharge current (I), gap voltage (V), pulse on time (TON), pressure (P) and speed (N) were chosen as the various input parameters. Three levels of values were chosen for each input parameter, whereas speed was chosen as the fixed parameter. The variation in the material removal rate (MRR), surface roughness (SR), surface morphology and elemental composition of the machined surface due to variation in the input parameters were analyzed in both dry and conventional mode. Better MRR, and surface roughness were observed in the work piece machined under conventional EDM process. The MRR is observed to be 84% more in the conventional mode when compared with dry EDM. Also, when compared to the dry EDM, about 15.33% better SR values is observed in the conventional EDM process.

Effect of SiC-Cu Electrode on Material Removal Rate, Tool Wear and Surface Roughness in EDM Process

2020 ◽  
Vol 38 (9A) ◽  
pp. 1406-1413
Author(s):  
Yousif Q. Laibia ◽  
Saad K. Shather
Keyword(s):  
Surface Roughness ◽  
Tool Wear ◽  
Material Removal Rate ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
304 Stainless Steel ◽  
Tool Electrode ◽  
Pulse Time ◽  
Edm Process

Electrical discharge machining (EDM) is one of the most common non-traditional processes for the manufacture of high precision parts and complex shapes. The EDM process depends on the heat energy between the work material and the tool electrode. This study focused on the material removal rate (MRR), the surface roughness, and tool wear in a 304 stainless steel EDM. The composite electrode consisted of copper (Cu) and silicon carbide (SiC). The current effects imposed on the working material, as well as the pulses that change over time during the experiment. When the current used is (8, 5, 3, 2, 1.5) A, the pulse time used is (12, 25) μs and the size of the space used is (1) mm. Optimum surface roughness under a current of 1.5 A and the pulse time of 25 μs with a maximum MRR of 8 A and the pulse duration of 25 μs.

Magnetic Field Assisted Electric Discharge Machining of Cryo-Treated Monel 400 Alloy

2015 ◽  
Vol 787 ◽  
pp. 371-375
Author(s):  
Rahul R. Jadhav ◽  
Vijaykumar S. Jatti ◽  
T.P. Singh
Keyword(s):  
Magnetic Field ◽  
External Magnetic Field ◽  
Tool Wear ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Cryogenic Treatment ◽  
Engineering Properties ◽  
Work Piece ◽  
Unconventional Machining ◽  
Edm Process

Monel alloys are pioneering materials which have exceptional engineering properties such as corrosion resistance, high toughness and show good response to cryogenic treatment. It finds uses in ship building, nuclear aerospace, missile and valve industries. These materials shows strain hardening effect which results in tool wear and in some cases tool breakage when machined by conventional methodshence, unconventional machining such as electrical discharge machining (EDM)discoverspurpose for machining of such materials. Researchers have recognized relation between electrical input process parameters of EDM process and output parameters of EDM process. But researchers have not investigated the influence of external magnetic field and cryo-treatment of work piece on EDM performance measures namely material removal rate (MRR) and tool wear rate (TWR). In vision of this the objective of present work was to study the effect of gap current, external magnetic field and cryogenic treatment of work part on MRR and TWR. Experiments were carried out by creating a 3 mm square hole on Monel400 alloys. Based on experimental results it was found that as gap current increases the MRR and TWR increases for untreated work part. For treated work part MRR increases and TWR decreases with increasein gap current. MRR and TWR increases with constant gap current for untreated work part, as magnetic field increases. For treated work part MRR increases and TWR decreases with increase in magnetic field at constant gap current.

scholarly journals Study on the Influence of Metallic Powder in Near-Dry Electric Discharge Machining

2020 ◽  
Vol 66 (4) ◽  
pp. 243-253 ◽  
Author(s):  
Sanjay Sundriyal ◽  
Vipin ◽  
Ravinderjit Singh Walia
Keyword(s):  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Dielectric Medium ◽  
Metallic Powder ◽  
Machining Process ◽  
Electric Discharge Machining ◽  
En 31 ◽  
Edm Process ◽  
Dry Electrical Discharge Machining

Near-dry electrical discharge machining (ND-EDM) is an eco-friendly process. In this study, an approach has been made to make the machining process more efficient than ND-EDM with the addition of metallic powder with the dielectric medium to machine EN-31 die steel. Powdermixed near-dry EDM (PMND-EDM) has several advantages over the ND-EDM or conventional electrical discharge machining (EDM) process, such as a higher material removal rate (MRR), fine surface finish (Ra), sharp cutting edge, lesser recast layer, and lower deposition of debris. The output response variables are MRR, Ra, residual stress (RS) and micro-hardness (MH) of the machined surfaces. Further study of the workpiece was performed, and a comparative study was conducted between ND-EDM and PMND-EDM. In this proposed method of machining, the MRR, Ra, and MH increased by 17.85 %, 16.36 %, and 62.69 % while RS was reduced by 56.09 %.

Dentale Implantatstrukturen aus CrCoMo/Near-dry EDM of CrCoMo dental implant structures

2020 ◽  
Vol 110 (11-12) ◽  
pp. 811-815
Author(s):  
Lisa Marie Rickerts ◽  
Tassilo-Maria Schimmelpfennig ◽  
Ivan Perfilov
Keyword(s):  
Dental Implant ◽  
High Precision ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Tool Electrode ◽  
Process Variables ◽  
Dry Edm ◽  
Edm Process ◽  
Erosion Zone

Die Funkenerosion wird in der Dentalindustrie zur Herstellung von hochpräzisem Zahnersatz aus CrCoMo eingesetzt. Dieser Beitrag stellt die Strategie und Technologie der halbtrockenen Funkenerosion von CrCoMo-Dentalbrücken vor. Als Dielektrikum kommt ein Wasser-Luft-Gemisch zum Einsatz, dass durch ein speziell entwickeltes Spülsystem durch die Kupfer-Werkzeugelektrode in die Erodierzone injiziert wird. Um die Effizienz des halbtrockenen Erodierprozesses zu erhöhen, werden die grundlegenden Zusammenhänge zwischen ausgewählten Prozessgrößen experimentell untersucht. Electrical discharge machining (EDM) is used in dental industry for the manufacturing of high-precision dentures from CrCoMo. This article presents the strategy and technology of near-dry EDM of CrCoMo dental bridges. A water-air mixture, which is injected through the copper tool electrode into the erosion zone by a specially developed flushing system is used as dielectric. In order to increase the efficiency of the near-dry EDM process, the basic relationships between the influencing process variables are investigated experimentally.

A REVIEW OF RECENT METHODS FOR TOOL WEAR REDUCTION IN ELECTRICAL DISCHARGE MACHINING

2020 ◽  
Vol 27 (12) ◽  
pp. 2030002 ◽  
Author(s):  
AMOLJIT SINGH GILL ◽  
SANJEEV KUMAR ◽  
JUJHAR SINGH ◽  
VIVEK AGGARWAL ◽  
SHUBHAM SHARMA
Keyword(s):  
Tool Wear ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Tool Electrode ◽  
Machining Processes ◽  
Dielectric Characteristics ◽  
Coated Tool ◽  
Ultrasonic Assisted ◽  
Edm Process

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.

Finite Element Modeling of Discharge Zone in Micro-EDM Process

2012 ◽  
Author(s):  
Jose Mathew ◽  
Deepak G. Dilip ◽  
Mathew J. Joseph ◽  
Basil Kuriachen
Keyword(s):  
Finite Element ◽  
Titanium Alloy ◽  
Removal Rate ◽  
Discharge Zone ◽  
Dielectric Fluid ◽  
Work Piece ◽  
Uniform Mesh ◽  
Tool Electrode ◽  
Micro Edm ◽  
Edm Process

Micro-EDM (μ-EDM) is a derived form of EDM process especially evolved to perform micro-machining. The μ-EDM process is based on the thermoelectric energy created between a work piece and an electrode submerged in a dielectric fluid. When the work piece and the electrode are separated by a specific small gap, a pulsed discharge occurs which removes material from the work piece through melting and evaporation. A thermo-electrical approach to model the temperature variation in the discharge gap using finite element method has been done so as to predict the temperature distribution in the discharge channel and find out the maximum temperatures acting on the work piece as well as the tool electrode and the subsequent material removal rate on the work piece. The temperature generated on the surface of the work piece depends upon the various properties of the conductor; as a result it varies depending on the conductor. An axi-symmetric two-dimensional model was used for modeling the region between the two electrodes. Tungsten and titanium alloy were the materials used for cathode and anode, respectively. A 60μm by 60μm region was taken for modeling the process. An uniform mesh of equal dimensions was made to carry out the modeling. The finite element results were compared with the results obtained by conducting experiments on titanium alloy using single spark generator device under the same discharge conditions that were given as input for the mathematical model. The MRR obtained agrees very well with the predicted MRR thus validating the model.

Investigation of the Spark Cycle Effect on Material Removal Rate in Wire Electrical Discharge Machining

Manufacturing ◽  
2003 ◽  
Author(s):  
Scott F. Miller ◽  
Albert J. Shih
Keyword(s):  
Process Parameters ◽  
Material Removal Rate ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Short Circuit ◽  
Wire Electrical Discharge Machining ◽  
Time Duration ◽  
Edm Process

The development of new, advanced engineering materials and the needs for precise and flexible prototype and low-volume production have made wire electrical discharge machining (EDM) an important manufacturing process to meet such demand. This research investigates the effect of spark on-time duration and spark on-time ratio, two important EDM process parameters, on the material removal rate (MRR) and surface integrity of four types of advanced material: porous metal foams, metal bond diamond grinding wheels, sintered Nd-Fe-B magnets, and carbon-carbon bipolar plates. An experimental procedure was developed. During the wire EDM, five types of constraints on the MRR due to short circuit, wire breakage, machine slide speed limit, and spark on-time upper and lower limits have been identified. An envelope of feasible EDM process parameters is created and compared across different work-materials. Applications of such process envelope to select process parameters for maximum MRR and for machining of micro features are presented.

Modeling of Dry-EDM Plasma Discharge

2020 ◽  
Author(s):  
Soham Mujumdar
Keyword(s):  
Heat Flux ◽  
Discharge Current ◽  
Plasma Discharge ◽  
Dielectric Medium ◽  
Air Plasma ◽  
Process Improvements ◽  
Dry Edm ◽  
Single Discharge ◽  
Balance Energy ◽  
Edm Process

Abstract There is a growing interest in developing the dry EDM process as a sustainable alternative to the conventional liquid dielectric-based EDM process. It is shown that the dry EDM process possesses advantages over the conventional process in terms of thermal damage, recast layer, and tool wear. However, there is a need to increase the productivity of the dry EDM process for its successful adaptation in the industry. This paper presents a model of dry EDM plasma discharge with air as the dielectric medium. The model uses global modeling (‘0D’) approach in which equations of mass balance, energy balance, and plasma expansion are solved simultaneously to obtain a time-dependent description of the plasma in terms of its composition, temperature, diameter, and heat flux to electrodes. The model includes reaction kinetics involving 622 reactions and 55 species to determine the air plasma composition. A single discharge dry EDM operation is successfully simulated using the model, and the effect of discharge current on the plasma is studied. An increase in the discharge current increases the electron density, temperature, and diameter of the plasma linearly, while heat flux to the workpiece increases exponentially. Overall, the model provides an essential tool to study the dry EDM process mechanisms at a fundamental level and devise methods for process improvements.

Experimental Study of Machining of Shape Memory Alloys Using Dry Micro Electrical Discharge Machining Process

2018 ◽  
Author(s):  
Sagil James ◽  
Sharadkumar Kakadiya
Keyword(s):  
Shape Memory Alloys ◽  
Shape Memory ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Dielectric Medium ◽  
Machining Process ◽  
Machining Processes ◽  
Micro Electrical Discharge Machining

Shape Memory Alloys are smart materials that tend to remember and return to its original shape when subjected to deformation. These materials find numerous applications in robotics, automotive and biomedical industries. Micromachining of SMAs is often a considerable challenge using conventional machining processes. Micro-Electrical Discharge Machining is a combination of thermal and electrical processes, which can machine any electrically conductive material at micron scale independent of its hardness. It employs dielectric medium such as hydrocarbon oils, deionized water, and kerosene. Using liquid dielectrics has adverse effects on the machined surface causing cracking, white layer deposition, and irregular surface finish. These limitations can be minimized by using a dry dielectric medium such as air or nitrogen gas. This research involves the experimental study of micromachining of Shape Memory Alloys using dry Micro-Electrical Discharge Machining process. The study considers the effect of critical process parameters including discharge voltage and discharge current on the material removal rate and the tool wear rate. A comparison study is performed between the Micro-Electrical Discharge Machining process with using the liquid as well as air as the dielectric medium. In this study, microcavities are successfully machined on shape memory alloys using dry Micro-Electrical Discharge Machining process. The study found that the dry Micro-Electrical Discharge Machining produces a comparatively better surface finish, has lower tool wear and lesser material removal rate compared to the process using the liquid as the dielectric medium. The results of this research could extend the industrial applications of Micro Electrical Discharge Machining processes.

Sign in / Sign up

Export Citation Format

Share Document