Modeling of Material Removal in Atomized Dielectric-Based Electrical Discharge Machining (EDM)

2019 ◽  
Author(s):  
Asif Tanveer ◽  
Shiv G. Kapoor ◽  
Soham S. Mujumdar
Keyword(s):  
Electrical Discharge ◽  
Material Removal ◽  
Film Flow ◽  
Electrical Discharge Machining ◽  
Dielectric Film ◽  
Machining Process ◽  
Spray Parameters ◽  
Melt Pool ◽  
Material Removal Model ◽  
Pool Formation

Abstract Atomized dielectric-based electrical discharge machining (EDM) is an emerging technology in which the dielectric between the electrodes is supplied in the form of a thin film using a spray atomizer. This novel machining process uses significantly less quantities of dielectric compared to the conventional EDM while resulting in higher material removal rates and better debris flushing. This paper presents a model-based investigation of the atomized dielectric-based EDM to study the effect of the dielectric film flow on material removal. A melt-pool formation and material removal model is developed to predict the material removal in terms of crater shapes during a single EDM discharge. The atomization spray parameters are varied in order to produce different dielectric film velocities. The model accurately captures the asymmetry in crater shapes caused by the dielectric film flow and predicts the crater diameter and depth, however, the model overestimates the crater sizes observed in experiments.

Mechanism of Debris Ejection in Atomized Dielectric-Based Electrical Discharge Machining

2020 ◽  
Vol 8 (4) ◽  
Author(s):  
Asif Tanveer ◽  
Shiv Kapoor
Keyword(s):  
Thin Film ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Dielectric Material ◽  
Machining Process ◽  
Spray Parameters ◽  
Debris Particles ◽  
Atomization Spray ◽  
Material Removal Model

Abstract Atomized dielectric-based electrical discharge machining (EDM) is a novel machining process in which a thin film of moving fluid resulting from a spray acts as the dielectric in the interelectrode gap. In addition to acting as the dielectric, the thin film also helps to flush the debris away from EDM crater features and requires very small quantity of fluid in doing so. This results in significantly less dielectric consumption compared to the conventional EDM while yielding higher material removal rates and better debris flushing. This paper presents a model-based investigation of the mechanism of debris flushing in atomized dielectric-based EDM. A material removal model is used to predict the amount of debris removed in terms of number of particles ejected during a single EDM discharge. The dielectric material properties and atomization spray parameters are varied in order to produce different ejection conditions and crater geometries, respectively. Particles are ejected from the bottom of crater geometries. The model captures the asymmetry in particle motion caused by the dielectric film flow and predicts the percentage of debris flushed away from the crater center. It is also observed that crater shape and size of debris particles play a role in the amount of debris flushed away.

Mechanism of Debris Ejection in Atomized Dielectric-Based Electrical Discharge Machining

2020 ◽  
Author(s):  
Asif Tanveer ◽  
S. G. Kapoor
Keyword(s):  
Thin Film ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Dielectric Material ◽  
Machining Process ◽  
Spray Parameters ◽  
Debris Particles ◽  
Atomization Spray ◽  
Material Removal Model

Abstract Atomized dielectric-based electrical discharge machining (EDM) is a novel machining process in which a thin film of moving fluid resulting from a spray acts as the dielectric in the interelectrode gap. In addition to acting as the dielectric, the thin film also helps to flush the debris away from EDM crater features and requires very small quantity of fluid in doing so. This results in significantly less dielectric consumption compared to the conventional EDM while yielding higher material removal rates and better debris flushing. This paper presents a model-based investigation of the mechanism of debris flushing in atomized dielectric-based EDM. A material removal model is used to predict the amount of debris removed in terms of number of particles ejected during a single EDM discharge. The dielectric material properties and atomization spray parameters are varied in order to produce different ejection conditions and crater geometries, respectively. Particles are ejected from the bottom of crater geometries. The model captures the asymmetry in particle motion caused by the dielectric film flow and predicts the percentage of debris flushed away from the crater center. It is also observed that crater shape and size of debris particles play a role in the amount of debris flushed away.

Optimization of μEDM process assisted with rotating magnetic pulling force and ultrasonic vibration

2021 ◽  
pp. 095440892098440
Author(s):  
Gurpreet Singh ◽  
DR Prajapati ◽  
PS Satsangi
Keyword(s):  
Ultrasonic Vibration ◽  
Material Removal Rate ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Machining Process ◽  
Micro Electrical Discharge Machining ◽  
Pulling Force ◽  
Tool Rotation

The micro-electrical discharge machining process is hindered by low material removal rate and low surface quality, which bound its capability. The assistance of ultrasonic vibration and magnetic pulling force in micro-electrical discharge machining helps to overcome this limitation and increase the stability of the machining process. In the present research, an attempt has been made on Taguchi based GRA optimization for µEDM assisted with ultrasonic vibration and magnetic pulling force while µEDM of SKD-5 die steel with the tubular copper electrode. The process parameters such as ultrasonic vibration, magnetic pulling force, tool rotation, energy and feed rate have been chosen as process variables. Material removal rate and taper of the feature have been selected as response measures. From the experimental study, it has been found that response output measures have been significantly improved by 18% as compared to non assisted µEDM. The best optimal combination of input parameters for improved performance measures were recorded as machining with ultrasonic vibration (U1), 0.25 kgf of magnetic pulling force (M1), 600 rpm of tool rotation (R2), 3.38 mJ of energy (E3) and 1.5 mm/min of Tool feed rate (F3). The confirmation trail was also carried out for the validation of the results attained by Grey Relational Analysis and confirmed that there is a substantial improvement with both assistance applied simultaneously.

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.

The effect of magnesium content on drilling of Al-Mg-Ti alloy by hole electrical discharge machining process

2020 ◽  
Vol 235 (1-2) ◽  
pp. 125-133
Author(s):  
Omer Eyercioglu ◽  
Kursad Gov
Keyword(s):  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Magnesium Content ◽  
Machining Process ◽  
Electrode Wear ◽  
Ti Alloy ◽  
Ti Alloys ◽  
Mg Content

This study presents an experimental investigation of small hole electrical discharge machining of Al-Mg-Ti alloys. A series of drilling operations were carried out for exploring the effect of magnesium content. Holes of 2 mm diameter and 15 mm depth were drilled using tubular single-hole rotary brass electrodes. The rates of material removal and electrode wear, surface roughness, overcut, average recast layer thickness, taper height and angle were studied for Al-Mg-Ti alloys contain 2%, 4%, 6%, 8%, 10%, 12%, and 14% Mg. The results show that the material removal rate is increasing with increasing Mg content while the rate of electrode wear is almost unchanged. Due to decreasing the melting temperature of the Al-Mg-Ti alloy with increasing Mg content, more metal melts and vaporizes during electrical discharge machining drilling. Therefore, more overcut and taper, thicker white layer, and rougher surfaces were measured for higher Mg content.

Influence of Process Parameters on Characteristics of Electrical Discharge Machining of PH17-4 Stainless Steel

2015 ◽  
Vol 14 (03) ◽  
pp. 189-202 ◽  
Author(s):  
V. Vikram Reddy ◽  
P. Madar Valli ◽  
A. Kumar ◽  
Ch. Sridhar Reddy
Keyword(s):  
Material Removal Rate ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Surface Hardness ◽  
Machining Process ◽  
Pulse On Time ◽  
Pulse Off Time ◽  
Off Time

In the present work, an investigation has been made into the electrical discharge machining process during machining of precipitation hardening stainless steel PH17-4. Taguchi method is used to formulate the experimental layout, to analyze the effect of each process parameter on machining characteristics and to predict the optimal choice for each electrical discharge machining process parameters namely, peak current, pulse on time and pulse off time that give up optimal process performance characteristics such as material removal rate, surface roughness, tool wear rate and surface hardness. To identify the significance of parameters on measured response, the analysis of variance has been done. It is found that parameters peak current and pulse on time have the significant affect on material removal rate, surface roughness, tool wear rate and surface hardness. However, parameter pulse off time has significant affect on material removal rate. Confirmation tests are conducted at their respective optimum parametric settings to verify the predicted optimal values of performance characteristics.

Comparative evaluation of powder-mixed and ultrasonic-assisted rough die-sinking electrical discharge machining based on pulse characteristics

2019 ◽  
Vol 233 (14) ◽  
pp. 2515-2530 ◽  
Author(s):  
R Rajeswari ◽  
MS Shunmugam
Keyword(s):  
Material Removal Rate ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Graphite Powder ◽  
Machining Process ◽  
Machined Surface ◽  
Ultrasonic Assisted ◽  
Pulse On Time

Electrical discharge machining is used in the machining of complicated shapes in hardened molds and dies. In rough die-sinking stage, attempts are made to enhance material removal rate with a consequential reduction in cycle time. Powder mix and ultrasonic assistance are employed in the electrical discharge machining process to create gap conditions favoring material removal. In the present work, experiments are carried out on hardened D3 die steel using full-factorial design based on three levels of voltage, current and pulse on time. The gap phenomena in graphite powder-mixed and ultrasonic-assisted rough electrical discharge machining are studied using a detailed analysis of pulse shapes and their characteristic trains. Two new parameters, namely, energy expended over a second ( E) and performance factor ( PF) denoting the ratio of energy associated with sparks to total discharge energy, bring out gap conditions effectively. In comparison with the conventional electrical discharge machining for the selected condition, it is seen that the graphite powder mixed in the dielectric enhances the material removal rate by 20.8% with E of 215 J and PF of 0.227, while these values are 179.8 J and 0.076 for ultrasonic-assisted electrical discharge machining with marginal reduction of 3.9%. Cross-sectional images of workpieces also reveal the influence of electrical discharge machining conditions on the machined surface. The proposed approach can be extended to different powder mix and ultrasonic conditions to identify condition favoring higher material removal.

Performance characterization of powder mixed wire electrical discharge machining technique for processing of Ti6Al4V alloy

2021 ◽  
pp. 095440892110607
Author(s):  
Sadananda Chakraborty ◽  
Souren Mitra ◽  
Dipankar Bose
Keyword(s):  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Ti6al4v Alloy ◽  
Machining Process ◽  
Wire Electrical Discharge Machining ◽  
Powder Concentration ◽  
Pulse Off Time ◽  
Off Time

Precision machining characteristics with high-dimensional accuracy make the material more adaptable towards the applications. The present study employs the powder mixed wire electrical discharge machining process to machine Ti6Al4V alloy material. In spite of limited drawbacks and enhanced output in the powder mixed wire electrical discharge machining process, the present problem has been formulated for improving the machining efficiency of Ti6Al4V. The impact of suspended powder characteristics on responses, that is, material removal rate and surface roughness, is examined throughout the process. The current investigation also focuses on the interaction effect of machining constraints along with Al2O3 abrasive mixed dielectric to achieve economical machining output for the Ti6Al4V material. An effort has been presented to obtain optimal solutions using the different methodologies, namely response surface methodology, grey relation analysis, and particle swarm optimization. The study reveals that discharge energy is deeply influenced by the peak current and pulse off time followed by powder concentration in the powder mixed wire electrical discharge machining process. The maximum material removal rate of 6.628 mm3/min and average surface finish of 1.386 μm are the outcome of the present study for a set of optimal machining settings, that is, pulse off time ( Toff) of 7.247 μs, pulse on time ( Ton) of 30 μs, peak current ( Ip) of 2 A, and powder concentration of 4 g/L. Finally, the proposed model has been verified that the hybrid particle swarm optimization technique has the highest adequate capability to achieve maximum output. Thus, the approach offered an enhancement on performance measures of Ti6Al4V alloy in the powder mixed wire electrical discharge machining process.

Development of the Cylindrical Wire Electrical Discharge Machining Process

2001 ◽  
Author(s):  
Jun Qu ◽  
Albert J. Shih ◽  
Ron Scattergood
Keyword(s):  
Surface Finish ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Machining Process ◽  
Free Form ◽  
Wire Electrical Discharge Machining ◽  
Wire Edm ◽  
Cylindrical Workpiece ◽  
Cylindrical Wire

Abstract Results of applying the wire Electrical Discharge Machining (EDM) process to generate precise cylindrical forms on hard, difficult-to-machine materials are presented. The design of an underwater rotary spindle is first introduced. The spindle is added to a conventional two-axis wire EDM machine to enable the generation of free-form cylindrical geometry. Mathematical models for material removal rate and surface finish in cylindrical wire EDM of the free-form cylindrical workpiece are derived. Experiments are conducted for cylindrical and 2D wire EDM of brass and carbide work-materials. Comparing to the conventional 2D wire EDM of the same work-material, higher maximum material removal rates could be achieved in the cylindrical wire EDM. The surface finish and roundness of parts generated by cylindrical wire EDM at different part rotational speeds and wire traverse speeds are measured and analyzed.

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