Machining of External Cylindrical Surfaces on a RAM Electrical Discharge Machine

2013 ◽  
Vol 554-557 ◽  
pp. 1800-1805 ◽  
Author(s):  
Laurenţiu Slătineanu ◽  
Margareta Coteaţă ◽  
Irina Besliu ◽  
Lorelei Gherman ◽  
Oana Dodun
Keyword(s):  
Test Piece ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Electrical Discharge Machine ◽  
Machining Process ◽  
Tool Electrode ◽  
Shape Error ◽  
Machined Surface ◽  
Electrode Tool ◽  
Shape Errors

As other nonconventional machining methods, the electrical discharge machining is applied when the workpieces materials are difficult to be machined by classical machining methods or the surfaces could not be obtained in efficient conditions by classical machining methods. Such a situation could appear, for example, when test pieces must be separated from materials whose machining by classical methods is difficult. Taking into consideration the necessity to detach a cylindrical test piece from a workpiece made of a high resistance metallic alloy, the problem of using the electrical discharge machining was formulated. An initial experimental test by using the common work motion of the tool electrode from up to down highlighted high shape errors, due to the accumulation in the work zone of the particles detached from the workpiece and from the tool electrode, as a consequence of electrical discharge machining process. A second set of experiments were developed, placing the test piece over the electrode tool and ensuring a work motion of workpiece from up to down; in this situation, a diminishing of the shape error was noticed. The second set of experiments highlighted a relatively reduced conicalness of the machined surface and a low decrease of the machining speed. as the penetration depth of the tool electrode in the workpiece increases, too.

Diminishing Shape Errors at Electrical Discharge Machining of External Cylindrical Surfaces

2013 ◽  
Vol 371 ◽  
pp. 305-309 ◽  
Author(s):  
Laurenţiu Slătineanu ◽  
Margareta Coteaţă ◽  
Lorelei Gherman ◽  
Irina Beşliu ◽  
Miroslav Radovanović ◽  
...  
Keyword(s):  
Experimental Observation ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Cylindrical Tube ◽  
Tool Electrode ◽  
Shape Error ◽  
Machined Surface ◽  
Shape Errors ◽  
Cylindrical Parts ◽  
Experimental Researches

Electrical discharge machining is a method that could be applied in order to detach cylindrical parts from a workpiece made of electroconductive material. If cylindrical tube is used as tool electrode, the machined surface could have a conical shape, due to the presence in the work gap of the electroconductive particles, detached from electrodes. Experimental researches were developed in order to obtain information concerning the shape error of machined surface. As a result of the experimental observation, improved technological solutions were identified and investigated. The experimental results proved certain possibilities of shape error decrease.

Small Diameter External Cylindrical Surfaces Obtained by Ram Electrical Discharge Machining

2014 ◽  
Vol 611-612 ◽  
pp. 650-655 ◽  
Author(s):  
Laurenţiu Slătineanu ◽  
Margareta Coteaţă ◽  
Hans Peter Schulze ◽  
Oana Dodun ◽  
Irina Besliu ◽  
...  
Keyword(s):  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Process Analysis ◽  
Electrical Discharge Machine ◽  
Small Diameter ◽  
Machining Process ◽  
Dielectric Fluid ◽  
Tool Electrode ◽  
Electrical Discharges ◽  
Pulse On Time

Electrical discharge machining uses the pulse electrical discharges generated between the closest asperities existing on the workpiece surface and the active surface of the tool electrode in dielectric fluid. Essentially, some distinct electrical discharge machining schemas could be used in order to obtain cylindrical external surfaces; within this research, one preferred a machining schema based on the use of a cooper plate in which there were small diameter holes, by taking into consideration the existence of a ram electrical discharge machine. The results of the machining process analysis were presented. A thin copper was considered to be used as tool electrode, in order to diminish the spurious electrical discharges, able to generate shape errors of the machined surface. Some experimental researches were developed by changing the sizes of the process input parameters. As output factors, the test piece and tool electrode masses decreases were considered. Power type empirical mathematical models were determined, in order to highlight the influence exerted by the pulse on time, off time and machining process duration on the output parameters values.

Research on Electrical Discharge Machining for Injection Mold of Automotive Connector

2012 ◽  
Vol 522 ◽  
pp. 17-20
Author(s):  
Wei Min Pan ◽  
Ke Ke Shi ◽  
Xian Qing Lei
Keyword(s):  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Tool Electrode ◽  
Injection Mold ◽  
Workpiece Material ◽  
Electrode Tool ◽  
Mating Surface ◽  
Plastic Components

Electrical discharge machining (EDM) processing is generally applied on the area of molding plastic component or mating surface required high accuracy. The areas determine the quality of the plastic components. The principle of EDM is based on the material vaporization of high potential difference across the workpiece and Tool electrode. Tool electrode and workpieces are discontiguous when the EDM processes. Because there is no mechanical contact, Hardness and strength of the workpiece material have minimal effect on the material removal rate .The application of EDM technology on injection mold of automotive connector is focused on in this paper. Processing of the complex cores is researched. The design and processing of the tool electrode have been completed in the meantime.

Experimental study of an electrostatic field–induced electrolyte jet electrical discharge machining process

2015 ◽  
Vol 231 (10) ◽  
pp. 1752-1759 ◽  
Author(s):  
Zhang Yaou ◽  
Han Ning ◽  
Kang Xiaoming ◽  
Zhao Wansheng ◽  
Xu Kaixian
Keyword(s):  
Electrostatic Field ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Electrochemical Machining ◽  
Machining Process ◽  
Cyclic Process ◽  
Tool Electrode ◽  
Series Of Experiments ◽  
Current Detection ◽  
Electrolyte Jet

In this study, a new electrostatic field–induced electrolyte jet electrical discharge machining method has been proposed, which can automatically generate the tool electrode. Then, a series of experiments have been carried out to reveal the machining mechanism and test the machining ability of this method. The continuous observation experiments and the online current detection experiments have demonstrated that the electrolyte jet discharge machining is a pulsing, dynamic and cyclic process. Moreover, the 20-min time long reverse polarity experiments on the silicon surface have revealed that the machining is an electrical discharge machining process during the negative polarity machining; however, in the positive polarity machining, it is a hybrid electrical discharge machining and electrochemical machining process. Furthermore, the craters as small as 2 µm in diameter on stainless steel and silicon are produced by this electrolyte jet electrical discharge machining, which has proved the micro-machining ability of this method.

scholarly journals Surface Roughness Analysis of H13 Steel during Electrical Discharge Machining Process Using Cu–TiC Sintered Electrode

Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 5943
Author(s):  
Arminder Singh Walia ◽  
Vineet Srivastava ◽  
Mayank Garg ◽  
Nalin Somani ◽  
Nitin Kumar Gupta ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Surface Quality ◽  
Electrical Discharge ◽  
Pulse Current ◽  
Electrical Discharge Machining ◽  
Machining Process ◽  
H13 Steel ◽  
Machined Surface ◽  
Machined Surface Quality ◽  
Semi Empirical

In electrical discharge machining (EDM), the machined surface quality can be affected by the excessive temperature generation during the machining process. To achieve a longer life of the finished part, the machined surface quality plays a key role in maintaining its overall integrity. Surface roughness is an important quality evaluation of a material’s surface that has considerable influence on mechanical performance of the material. Herein, a sintered cermet tooltip with 75% copper and 25% titanium carbide was used as tool electrode for processing H13 steel. The experiments have been performed to investigate the effects of EDM parameters on the machined surface roughness. The findings show that, as the pulse current, pulse length, and pulse interval are increased, the surface roughness tends to rise. The most significant determinant for surface roughness was found to be pulse current. A semi-empirical surface roughness model was created using the characteristics of the EDM technique. Buckingham’s theorem was used to develop a semi-empirical surface roughness prediction model. The semi-empirical model’s predictions were in good agreement with the experimental studies, and the built empirical model based on physical features of the cermet tooltip was tested using dimensional analysis.

Surface Study in a Non-conventional (Electrical Discharge Machining) Process for Grade 6 Titanium Material

2014 ◽  
Vol 68 (1) ◽  
Author(s):  
Md. Ashikur Rahman Khan ◽  
M. M. Rahman
Keyword(s):  
Surface Roughness ◽  
Process Parameters ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Machining Process ◽  
Machined Surface ◽  
Titanium Material ◽  
Pulse On Time ◽  
Pulse Off Time ◽  
Off Time

Electrical discharge machining (EDM) produces complex shapes and permits high-precision machining of any hard or difficult-to-cut materials. The performance characteristics such as surface roughness and microstructure of the machined face are influenced by numerous parameters. The selection of parameters becomes complicated. Thus, the surface roughness (Ra) and microstructure of the machined surface in EDM on Grade 6 titanium alloy are studied is this study. The experimental work is performed using copper as electrode material. The polarity of the electrode is maintained as negative. The process parameters taken into account in this study are peak current (Ip), pulse-on time (Ton), pulse-off time (Toff), and servo-voltage (Sv). A smooth surface finish is found at low pulse current, small on-time and high off-time. The servo-voltage affects the roughness diversely however, a finish surface is found at 80 V Sv. Craters, cracks and globules of debris are appeared in the microstructure of the machined part. The size and degree of craters as well as cracks increase with increasing in energy level. Low discharge energy yields an even surface. This approach helps in selecting proper process parameters resulting in economic EDM machining. 

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.

Evaluation of Electrical Discharge Machining Performance on Al (6351)–SiC–B4C Composite

2019 ◽  
pp. 109-124
Author(s):  
Uthayakumar M. ◽  
Suresh Kumar S. ◽  
Thirumalai Kumaran S. ◽  
Parameswaran P.
Keyword(s):  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Research Work ◽  
Machining Process ◽  
Electrode Wear ◽  
Machining Parameters ◽  
Machining Performance ◽  
Machined Surface ◽  
Output Performance ◽  
B4c Particles

Electrical discharge machining (EDM) process is a non-conventional machining process used for the material which are difficult to machine. In this research work, an attempt has been made to determine the influence of Boron Carbide (B4C) particles on the machinablity of the Al (6351) alloy reinforced with 5 wt. % Silicon Carbide (SiC) Metal Matrix Composite (MMC) through EDM. Influence of machining parameters such as pulse current (I), pulse on time (Ton), duty factor (τ), and gap voltage (V) on affecting the output performance characteristics namely Electrode Wear Ratio (EWR), Surface Roughness (SR) and Power Consumption (PC) which are studied. The result shows that the addition of B4C particles significantly affects the machinablity of the composite, with a contribution of 1.6% on EWR, 3.5% on SR and 19.8% on PC. The crater, recast layer formation, and Heat Affected Zone (HAZ) in the machined surface of the composite are also reported in detail.

Electrode Tool Wear at Electrical Discharge Machining

2012 ◽  
Vol 504-506 ◽  
pp. 1189-1194 ◽  
Author(s):  
Laurenţiu Slătineanu ◽  
Hans Peter Schulze ◽  
Oana Dodun ◽  
Margareta Coteaţă ◽  
Lorelei Gherman ◽  
...  
Keyword(s):  
Cross Section ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Experimental Tests ◽  
Machining Process ◽  
Electrode Wear ◽  
Electrical Discharges ◽  
Workpiece Material ◽  
Electrode Tool ◽  
Theoretical Considerations

As consequence of the development of electrical discharge machining process, the electrode is affected by wear; knowing the evolution of the electrode wear, a better estimation of its service life is possible. It is expected that the electrode wear depends on the energy of the electrical discharges and the mass of the electrode. It is known also that the nature of the workpiece material exerts influence on the evolution of the electrode wearing process. In the paper, some theoretical considerations are used to highlight the above mentioned aspects. A set of experimental tests was designed and developed in order to highlight the influence exerted by the nature of the workpiece material and by the size of the cross section of the electrode, respectively, on the electrode wear. Empirical mathematical models corresponding to the evolution of the electrode wear were established.

Surface Morphology and Corrosion Behavior in Nano PMEDM

2016 ◽  
Vol 724 ◽  
pp. 61-65 ◽  
Author(s):  
Ahmad Majdi Abdul-Rani ◽  
Alexis Mouangue Nanimina ◽  
Turnad Lenggo Ginta
Keyword(s):  
Titanium Alloy ◽  
Corrosion Rate ◽  
Surface Morphology ◽  
Surface Quality ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Machining Process ◽  
Application Process ◽  
Machined Surface ◽  
Conventional Machining

This research study was conducted to investigate the effect of nanoaluminum powder mixed electrical discharge machining (PMEDM) on surface morphology and corrosion rate of titanium alloy material. The development of devices such as implants in biomedical engineering application nowadays requires materials having good mechanical and physical properties. Conventional machining process of titanium as implant is a challenge resulting relative poor surface quality. Even using electrical discharge machining (EDM) which is non-conventional machining process there are limitations including machined surface alteration with relative poor machined surface quality, low corrosion resistance and. PMEDM is hypothesized to address the above mentioned problems. In this study, PMEDM on titanium alloy using nanoaluminum powder and copper-tungsten electrode was assessed to investigate the improvement for implant application. Process parameters used are peak-current, ON-time, gap voltage and powder concentration. Surface morphology and average corrosion arte are selected output responses. Results showed that Surface morphology of PMEDM machined surface is significantly improved. PMEDM marginally enhanced corrosion rate of biomedical grade titanium alloy.

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