Parametric Approach Model for Determining Electrical Discharge Machining (EDM) Conditions: Effect of Cutting Parameters on the Surface Integrity
TL;DR: In this article, a simple and easily understandable model was proposed for predicting the relative importance of different factors (composition of the steels and Electro Discharge Machining processing conditions) in order to obtain an efficient pieces.
Abstract: Electrical discharge machining (EDM) is one of the earliest non-traditional machining processes. EDM process is based on thermoelectric energy between the work piece and an electrode. There are various types of products which can be produced by using the EDM such as dies and moulds. Today many parts used in aerospace and automotive industry and also final processes of surgical components can be finished by EDM process. A simple and easily understandable model was proposed for predicting the relative importance of different factors (composition of the steels and Electro Discharge Machining processing conditions) in order to obtain an efficient pieces. A detail application on the tool steels machined by EDM was given in this study. This model is based on thermal, metallurgical and mechanical and also in situ test conditions. It gives detail information on the effect of electrochemical parameters on the surface integrity and sub-surface damage of the material (Heat Affected Zone, HAZ), the level of residual stresses, and the surface texture. This approach is an efficient way to separate the responsibilities of the steel maker and machining process designer for increasing the reliability of the machined structures.
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TL;DR: In this paper, the performance of the electrical discharge machining (EDM) process is evaluated in terms of material removal rate, relative wear ratio and surface roughness of the work piece.
116 citations
TL;DR: In this paper, an attempt is made to relate the globule formation on the machined surface, with the machining current, and the white layer thickness, globule diameter and interglobule distance are found to increase with the increase in electric current.
Abstract: Electric discharge machining (EDM) produces a recast/white layer on the surface of the machined workpiece. Machining with EDM generally produces a higher surface roughness as compared to conventional machining processes. The operating parameters in EDM, i.e., “current”, “voltage”, “on time” and “off time” are directly related with the white layer formation, its thickness, morphology and roughness. Machining of Al 6061 T6 cylinders is performed on die-sinking EDM machine with varying electric current values to determine its effect on surface morphology in the case of aluminum alloy. Material removal rate versus current is determined for different current values. An attempt is made to relate the globule formation on the machined surface, with the machining current. Scanning electron microscopy, optical microscopy and material composition study through energy dispersive spectrography are performed. The white layer thickness, globule diameter and inter-globule distance are found to increase with the increase in electric current.
66 citations
TL;DR: In this article, the authors used the same value of fraction of energy transferred to electrodes for all machining parameters in their models for numerically calculating the volume and geometry of the crater formed.
35 citations
TL;DR: In this paper, the effects of electrical parameters: pulse-on-time and current on three performance measures (material removal rate, microstructures and electrode wear rate), using distilled water and kerosene as dielectrics was performed.
Abstract: Electrical discharge machining is a non-traditional machining method broadly employed in industries for machining of parts that have typical profiles and require great accuracy. This paper investigates the effects of electrical parameters: pulse-on-time and current on three performance measures (material removal rate, microstructures and electrode wear rate), using distilled water and kerosene as dielectrics. A comparison between dielectrics for the machining of aluminum 6061 T6 alloy material in terms of performance measures was performed. Aluminum 6061 T6 alloy material was selected, because of its growing use in the automotive and aerospace industrial sectors. The experimental sequence was designed using Taguchi technique of L9 orthogonal array by changing three levels of pulse-on-time and current, and test runs were performed separately for each dielectric. The results obtained show that greater electrode wear rate (EWR) and higher material removal rate (MRR) were achieved with distilled water when compared with kerosene. These greater EWR and MRR responses can be attributed to the early breakage of the weak oxide and carbide layers formed on the tool and alloy material surfaces, respectively. The innovative contributions of this study include, but are not limited to, the possibility of machining of aluminum 6061 T6 alloy with graphite electrode to enhance machinability and fast cutting rate employing two different dielectrics.
19 citations
TL;DR: In this article, the optimization of surface roughness and recast layer thickness of a WEDM process of AISI D2 steel was investigated by using Taguchi method, grey relational analysis and fuzzy logic.
Abstract: In this paper, the optimization of surface roughness and recast layer thickness of a WEDM process of AISI D2 steel was investigated by using Taguchi method, grey relational analysis and fuzzy logic. The experiments were conducted under varying flushing pressure, on time, open voltage, off time and servo voltage. An orthogonal array, signal-to-noise (S/N) ratio, grey relational analysis, grey-fuzzy reasoning grade and analysis of variance were employed to the study of the multiple performance characteristics. Experimental results have shown that machining performance characteristics in WEDM process of AISI D2 steel can be improved effectively through the combination of Taguchi method, grey relational analysis and fuzzy logic.
12 citations
References
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TL;DR: In this paper, a study has been made to optimize the process parameters of powder mixed electrical discharge machining (PMEDM), and the results identify the most important parameters to maximize material removal rate and minimize surface roughness.
402 citations
"Parametric Approach Model for Deter..." refers background in this paper
...Since EDM has been an indispensable operation in the manufacturing processes, it has been in the last few years the center of interest of several researchers [1–19]....
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TL;DR: In this article, the results of an experimental investigation carried out to study the effects of machining parameters such as pulsed current on material removal rate, diameteral overcut, electrode wear, and surface roughness in electric discharge machining of En-31 tool steel (IS designation: T105 Cr 1 Mn 60) hardened and tempered to 55 HRc.
385 citations
"Parametric Approach Model for Deter..." refers methods in this paper
...The parameters optimisation in some particular theoretical models related to the complex EDM phenomena was been investigated based on the Tagushi method by Ramakrishnan et al [12] they found that the increase in the exposure time induced sparks more uniform and more stable what is necessary to reduce the Electrode Wear Ratio EWR and roughness and that the increasing of the wire tension reduced its vibration and improves the surface quality of the machined part....
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...phenomena was been investigated based on the Tagushi method by Ramakrishnan et al [12] they found that the increase in the exposure time induced sparks more uniform and more stable what is necessary to reduce the Electrode Wear Ratio EWR and roughness and that the increasing of the wire tension reduced its vibration and improves the surface quality of the machined part....
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TL;DR: In this article, the authors developed an effective methodology to determine the optimum cutting conditions leading to minimum surface roughness in milling of mold surfaces by coupling response surface methodology (RSM) with a developed GA.
373 citations
"Parametric Approach Model for Deter..." refers background in this paper
...Since EDM has been an indispensable operation in the manufacturing processes, it has been in the last few years the center of interest of several researchers [1–19]....
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TL;DR: In this article, the relationship between EDM parameters and surface cracks was studied by using a full factorial design, based upon discharge current and pulse-on time parameters, and established a crack prediction map, and indicated whether or not cracks are likely to form for a given pulse-ON and pulse current combination.
301 citations
TL;DR: In this paper, a multi response optimization method using Taguchi's robust design approach is proposed for wire electrical discharge machining (WEDM) operations, where the machining parameters are optimized with the multi response characteristics of the material removal rate, surface roughness, and wire wear ratio.
Abstract: In this present study a multi response optimization method using Taguchi’s robust design approach is proposed for wire electrical discharge machining (WEDM) operations. Experimentation was planned as per Taguchi’s L16 orthogonal array. Each experiment has been performed under different cutting conditions of pulse on time, wire tension, delay time, wire feed speed, and ignition current intensity. Three responses namely material removal rate, surface roughness, and wire wear ratio have been considered for each experiment. The machining parameters are optimized with the multi response characteristics of the material removal rate, surface roughness, and wire wear ratio. Multi response S/N (MRSN) ratio was applied to measure the performance characteristics deviating from the actual value. Analysis of variance (ANOVA) is employed to identify the level of importance of the machining parameters on the multiple performance characteristics considered. Finally experimental confirmation was carried out to identify the effectiveness of this proposed method. A good improvement was obtained.
246 citations
"Parametric Approach Model for Deter..." refers background in this paper
...Boileau et al [11] pointed out that the composition of metal has a significant effect on the rate of dissolution but the composition of the solution of EDM (NaCl, NaF, NaBr) didn’t appear to have any significant effect on the dissolution speed of metals....
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