Performance Evaluation on Cryogenic Cooling of Electrode in Electrical Discharge Machining in AISI D2 Steel

2013 ◽  
Author(s):  
M. Pradeep Kumar ◽  
S. Vinoth Kumar
Keyword(s):  
Surface Roughness ◽  
Current Pulse ◽  
Discharge Current ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Electrode Wear ◽  
Machined Surface ◽  
Aisi D2 ◽  
Pulse On Time ◽  
D2 Steel

This research has been conducted to evaluate the performance of the Liquid Nitrogen (LN2) cooling of copper electrode in electrical discharge machining (EDM) on AISI D2 steel. The experimental process parameter such as discharge current, pulse on time and gap voltage were varied to explore their effects on machining performance, including the electrode wear and surface roughness. It was found that for electrode wear, discharge current, pulse on time, and gap voltage has the most significant effect, while the pulse on time and discharge current have the most significant effect on surface roughness. Analysis on the influence of cooling responses has been carried out and presented in this study. It was found that the electrode wear reduced up to 18% during LN2 cooling. Surface roughness was also significantly reduced while machining with LN2 electrode cooling. Scanning electron microscope (SEM) analysis was carried out to study the surface characteristics of machined surface. EDMed machined surface was also acceptable in LN2 cooling of the electrode.

scholarly journals Analysis, predictive modelling and multi-response optimization in electrical discharge machining of Al-22%SiC metal matrix composite for minimization of surface roughness and hole overcut

2020 ◽  
Vol 7 ◽  
pp. 20 ◽  
Author(s):  
Subhashree Naik ◽  
Sudhansu Ranjan Das ◽  
Debabrata Dhupal
Keyword(s):  
Surface Roughness ◽  
Metal Matrix Composite ◽  
Matrix Composite ◽  
Discharge Current ◽  
Metal Matrix ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Machining Parameters ◽  
Response Optimization ◽  
Pulse On Time

Due to the widespread engineering applications of metal matrix composites especially in automotive, aerospace, military, and electricity industries; the achievement of desired shape and contour of the machined end product with intricate geometry and dimensions that are very challenging task. This experimental investigation deals with electrical discharge machining of newly engineered metal matrix composite of aluminum reinforced with 22 wt.% of silicon carbide particles (Al-22%SiC MMC) using a brass electrode to analyze the machined part quality concerning surface roughness and overcut. Forty-six sets of experimental trials are conducted by considering five machining parameters (discharge current, gap voltage, pulse-on-time, pulse-off-time and flushing pressure) based on Box-Behnken's design of experiments (BBDOEs). This article demonstrates the methodology for predictive modeling and multi-response optimization of machining accuracy and surface quality to enhance the hole quality in Al-SiC based MMC, employing response surface methodology (RSM) and desirability function approach (DFA). Finally, a novel approach has been proposed for economic analysis which estimated the total machining cost per part of rupees 211.08 during EDM of Al-SiC MMC under optimum machining conditions. Thereafter, under the influence of discharge current several observations are performed on machined surface morphology and hole characteristics by scanning electron microscope to establish the process. The result shows that discharge current has the significant contribution (38.16% for Ra, 37.12% in case of OC) in degradation of surface finish as well as the dimensional deviation of hole diameter, especially overcut. The machining data generated for the Al-SiC MMC will be useful for the industry.

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. 

Optimization of machining parameters in chromium-additive mixed electrical discharge machining of the AA7075/5%B4C composite

2021 ◽  
pp. 095440892110317
Author(s):  
Vineet Dubey ◽  
Anuj K Sharma ◽  
Balbir Singh
Keyword(s):  
Surface Roughness ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Process Condition ◽  
Dielectric Fluid ◽  
Optimum Process ◽  
Machining Parameters ◽  
Machined Surface ◽  
Pulse On Time ◽  
Pulse Off Time

The present study establishes the optimum process condition for additive mixed electrical discharge machining of Al7075–5%B4Cp metal matrix composite by performing experimental investigation. The suspension of chromium particles in a dielectric fluid is used as an additive. The input process parameters selected for experimentation are specifically pulse on-time, gap voltage, pulse off-time and peak current, for analysing their influence on wear of the tool along with surface roughness of the composite. Comparative study of the machined surface is done by analysing microstructures, cracks and recast layers formed at different settings of input parameters using a scanning electron microscope. Rise in amount of current and pulse on-time led to increased height of the recast layer generated on the surface of the machined workpiece. Furthermore, a confirmatory experiment was performed at the optimal setting. The result revealed an error of 5.5% and 7.5% between experimental and predicted value of tool wear rate and surface roughness.

Parametric Optimization of Boron Carbide Powder Added Electrical Discharge Machining of Titanium Alloy

2014 ◽  
Vol 592-594 ◽  
pp. 678-683 ◽  
Author(s):  
Murahari Kolli ◽  
Adepu Kumar
Keyword(s):  
Titanium Alloy ◽  
Boron Carbide ◽  
Current Pulse ◽  
Discharge Current ◽  
Electrical Discharge ◽  
Electrical Discharge Machining ◽  
Taguchi Technique ◽  
Discharge Current Pulse ◽  
Powder Concentration ◽  
Pulse On Time

The present study deals with the Taguchi technique applied to determine the optimal process parameters of Boron Carbide (B4C) powder mixed electrical discharge machining (EDM) of Titanium alloy. The performance characteristics like material removal rate (MRR) and surface roughness (SR) were experimentally explored for various input parameters such as discharge current, pulse on time, pulse off time and B4C powder concentration in dielectric fluid. The planned optimal setting parameters were conducted and verified through experiments and analyzed using Taguchi technique. Analysis of variance (ANOVA) revealed that discharge current, pulse on time and B4C powder concentration in dielectric are most important parameters affecting both the performance parameters.

scholarly journals Investigation on Material Removal Rate and Surface Finish in Electrical Discharge Machining of AA 6061-B4C Composite Material

2021 ◽  
Vol 23 (12) ◽  
pp. 224-235
Author(s):  
N. Ethiraj ◽  
◽  
T. Sivabalan ◽  
Saibal Chatterjee ◽  
Seeramsetti Mahesh ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Composite Material ◽  
Process Parameters ◽  
Material Removal Rate ◽  
Discharge Current ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Pulse On Time

One of the non-conventional techniques of metal removal manufacturing processes is electrical discharge machining (EDM). The objective of this paper is to prepare a composite material consisting of a matrix of Aluminium AA 6061 alloy and Boron carbide (B4C) as reinforcement and investigate the output responses, the material removal rate, the quality of the surface formed and overcut during EDM process. The process parameters discharge current, Pulse on time and Duty cycle along with the weight % of B4C are considered for investigation to investigate the output responses such as material removal rate, surface roughness and overcut. From the experimental results, it is observed that the weight % of reinforcement has more influence on the material removal rate. The parameters discharge current and pulse-on-time plays an important role in reducing the surface roughness and overcut. Microstructural study helps in understanding the effect of process parameters on the output responses.

Parametric Optimization of Wire Cut Electrical Discharge Machining on Al-9% PAC Composites using Desirability Approach

2018 ◽  
Vol 10 (6) ◽  
Author(s):  
G. Ramanan ◽  
R. Elangovan
Keyword(s):  
Surface Roughness ◽  
Material Removal Rate ◽  
Discharge Current ◽  
Electrical Discharge ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Pulse On Time ◽  
Pulse Off Time ◽  
Off Time

In aerospace and automobile industries manufacturing complex structures using un-conventional machining is increased due to their precision and accuracy. This research investigates the influence of input parameters such as discharge current, pulse on time, pulse off time and servo speed rate of wire cut electrical discharge machining (WEDM) on material removal rate and surface roughness using Box Behnken design supported with response surface methodology. Aluminium alloy 7075 reinforced with 9 % wt. of activated carbon composite is used to carry out the machining process. Most influencing parameters are subjected as the conductive and non-conductive parameters in WEDM process. To find out the significant influence of each factor, analysis of variance was performed. The mathematical model is established using desirability technique and then the optimal machining parameters are determined. The best achieved WEDM performances - material removal rate and surface roughness are 10.46 mm3/min and 3.32μm respectively, by using optimum machining conditions - discharge current 2000mA, pulse on time 8.9µs, pulse off time 25µs and servo speed rate 150rpm at 0.8597 desirability value.

Study on Machinabilty of Al2O3 Ceramic Composite in EDM Using Response Surface Methodology

2011 ◽  
Vol 133 (2) ◽  
Author(s):  
K. M. Patel ◽  
Pulak M. Pandey ◽  
P. Venkateswara Rao
Keyword(s):  
Surface Roughness ◽  
Response Surface Methodology ◽  
Response Surface ◽  
Current Pulse ◽  
Duty Cycle ◽  
Discharge Current ◽  
Ceramic Composite ◽  
Electrode Wear ◽  
Discharge Current Pulse ◽  
Pulse On Time

Electric discharge machining (EDM) has been proven as an alternate process for machining complex and intricate shapes from the conductive ceramic composites. Al2O3 based electrodischarge machinable Al2O3–SiCw–TiC ceramic composite is a potential substitute for traditional materials due to their high hardness, excellent chemical, and mechanical stability under a broad range of temperature, and high specific stiffness. The right selection of the machining condition is the most important aspect to take into consideration in the EDM. The present work correlates the inter-relationships of various EDM machining parameters, namely, discharge current, pulse-on time, duty cycle, and gap voltage on the metal removal rate (MRR), electrode wear ratio (EWR), and surface roughness using the response surface methodology (RSM) while EDM of Al2O3–SiCw–TiC ceramic composite. Analysis of variance is used to study the significance of process variables on MRR, EWR, and surface roughness. The experimental results reveal that discharge current, pulse-on time, and duty cycle significantly affected MRR and EWR, while discharge current and pulse-on time affected the surface roughness. The validation of developed models shows that the MRR EWR and surface roughness of EDM of Al2O3–SiCw–TiC ceramic can be estimated with reasonable accuracy using the second-order models. Finally, trust-region method for nonlinear minimization is used to find the optimum levels of the parameters. The surface and subsurface damage have also been assessed and characterized using scanning electron microscopy. This study reveals that EDMed material unevenness increases with discharge current and pulse-on time.

scholarly journals Surface Modification Using Assisting Electrodes in Wire Electrical Discharge Machining for Silicon Wafer Preparation

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1355
Author(s):  
Chunliang Kuo ◽  
Yupang Nien ◽  
Anchun Chiang ◽  
Atsushi Hirata
Keyword(s):  
Surface Roughness ◽  
Surface Modification ◽  
Electrical Discharge ◽  
Polycrystalline Silicon ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Wire Electrical Discharge Machining ◽  
Electrode Thickness ◽  
Machined Surface ◽  
Pulse On Time

This paper outlines notable advances in the wire electrical discharge machining of polycrystalline silicon workpieces for wafer preparation. Our use of assisting electrodes permits the transfer of aluminum particles to the machined surface of the polycrystalline silicon workpieces, to enhance conductivity and alter surface topography regardless of the silicon’s crystallographic structure and diamond-type lattice. This in-process surface modification technique was shown to promote material removal and simultaneously preserve the integrity of the machined surfaces with preferable surface textures. In the validation experiment, the 25 mm-thick assisting electrodes deposited a notable concentration of aluminium on the machined surface (~3.87 wt %), which greatly accelerated the rate of material removal (~9.42 mg/s) with minimal surface roughness (Sa ~5.49 μm) and moderate skewness (−0.23). The parameter combination used to obtain the optimal surface roughness (Sa 2.54 μm) was as follows: open voltage (80 V), electrical resistance (1.7 Ω), pulse-on time (30 μs), and electrode thickness (15 mm). In multiple objective optimization, the preferred parameter combination (open voltage = 80 V, resistance = 1.4 Ω, pulse-on time = 60 μs, and assisting electrode thickness = 25 mm) achieved the following appreciable results: surface modification of 3.26 ± 0.61 wt %, material removal rate of 7.08 ± 2.2 mg/min, and surface roughness of Sa = 4.3 ± 1.67 μm.

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