Influence of process parameters of electrical discharge machining on MRR, TWR and surface roughness: A review

Wire electrical discharge machining is one of the important non-traditional machining processes for machining difficult to machine materials. It involves the removal of material by the discrete electric discharges produced between the inter electrode gap of continuously moving wire electrode and the work piece. The ability to produce intricate profiles on materials irrespective of the mechanical properties made this process to be widely used in industries. The present study investigates the relationship of various process parameters in WEDM of AISI 202 stainless steel with brass electrode.The experiments were planned according to Taguchi’s L18 orthogonal array and experimental models were developed. The important process parameters identified for the present study were pulse on time, peak current, pulse off time, wire feed, wire tension, dielectric flushing pressure, servo feed and gap voltage. The surface roughness of the machined surface was measured as the process performance measure. Analysis of variance test has also been carried out to check the adequacy of the developed models and to identify the level of significance of each process parameters. In addition to the developed models, ABC optimization has been performed to identify the optimum parameter combination for minimum surface roughness and the obtained optimal process parameters are peak current 11 A, pulse on time 100 μs, pulse off time 49 μs, wire feed 4 m/min, wire tension 10 N, flushing pressure 12 kg/cm2, servo feed 2100 mm/min and set gap voltage 30 V. Finally the results were verified with the experimental results and found that they are in good agreement.

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

Jurnal Teknologi ◽

10.11113/jt.v68.1670 ◽

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.

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Parameter optimization and experimental study on wire electrical discharge machining of porous Ni40Ti60 alloy

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405415577710 ◽

2015 ◽

Vol 231 (6) ◽

pp. 956-970 ◽

Cited By ~ 31

Author(s):

Neeraj Sharma ◽

Tilak Raj ◽

Kamal Kumar Jangra

Keyword(s):

Process Parameters ◽

Electrical Discharge ◽

Electrical Discharge Machining ◽

Machining Process ◽

Wire Electrical Discharge Machining ◽

Influence Of Process Parameters ◽

Work Surface ◽

Pulse On Time ◽

Pulse Off Time ◽

Response Variables

NiTi is a shape memory alloy, mostly employed in cardiovascular stents, orthopedic implants, orthodontic wires, micro-electromechanical systems and so on. The effective and net shape machining of NiTi is very critical for excellent response of this material in medical and other applications. The present experimental work on wire electrical discharge machining process identifies the influence of process parameters that affect the cutting rate, dimensional shift and surface roughness while machining of porous nickel–titanium (Ni40Ti60) alloy. Porous Ni40Ti60 alloy was produced in-house using powder metallurgy technique. Response surface methodology–based central composite rotatable design has been used for the planning of experiments on wire electrical discharge machining. Empirical relations have been developed between the process parameters (pulse on-time, pulse off-time, servo voltage and peak current) and response variables. Desirability approach has been used for optimizing the three response variables simultaneously. Confirmation experiments were also performed at the optimized settings and reflect a close agreement between the predicted and experimental values (percentage error varies from −6.13% to +6.85%). Using wire electrical discharge machining, NiTi alloy can be machined easily and successfully in single-cutting operation, but after the first cut in wire electrical discharge machining, a surface projection appears on work surface which is the unmachined material on work surface.

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Influence of process parameters in electrical discharge machining on H13 die steel

Heliyon ◽

10.1016/j.heliyon.2019.e01813 ◽

2019 ◽

Vol 5 (6) ◽

pp. e01813 ◽

Cited By ~ 5

Author(s):

M.M. Bahgat ◽

A.Y. Shash ◽

M. Abd-Rabou ◽

I.S. El-Mahallawi

Keyword(s):

Process Parameters ◽

Electrical Discharge ◽

Electrical Discharge Machining ◽

Influence Of Process Parameters ◽

Die Steel ◽

H13 Die Steel

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Experimental investigations on surface integrity issues of Inconel-690 during wire-cut electrical discharge machining process

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405416654092 ◽

2016 ◽

Vol 232 (4) ◽

pp. 731-741 ◽

Cited By ~ 7

Author(s):

M Sreenivasa Rao ◽

N Venkaiah

Keyword(s):

Surface Roughness ◽

Layer Thickness ◽

Process Parameters ◽

Electrical Discharge ◽

Electrical Discharge Machining ◽

Recast Layer ◽

Machining Process ◽

Micro Hardness ◽

Recast Layer Thickness ◽

Inconel 690

Nickel-based alloys are finding a wide range of applications due to their superior properties of maintaining hardness at elevated temperatures, low thermal conductivity and resistance to corrosion. These materials are used in aircraft, power-generation turbines, rocket engines, automobiles, nuclear power and chemical processing plants. Machining of such alloys is difficult using conventional processes. Wire-cut electrical discharge machining is one of the advanced machining processes, which can cut any electrically conductive material irrespective of its hardness. One of the major disadvantages of this process is formation of recast layer as it affects the properties of the machined surfaces. In this study, experimental investigation has been carried out to study the effect of wire-cut electrical discharge machining process parameters on micro-hardness, surface roughness and recast layer while machining Inconel-690 material. Interestingly, hardness of the machined surface was found to be lower than that of the bulk material. The micro-hardness and recast layer thickness are inversely related to the variation of process parameters. Recast layer thickness, surface roughness and hardness of the wire-cut electrical discharge machined surfaces of Inconel-690 are found to be in the range of 10–50 µm, 0.276–3.253 µm and 122–171 HV, respectively, for different conditions. The research findings and the data generated for the first time on hardness and recast layer thickness for Inconel-690 will be useful to the industry.

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Analysis and Optimization of the Machining Characteristics of High-Volume Content SiCp/Al Composite in Wire Electrical Discharge Machining

Crystals ◽

10.3390/cryst11111342 ◽

2021 ◽

Vol 11 (11) ◽

pp. 1342

Author(s):

Hongzhi Yan ◽

Bakadiasa Djo Kabongo ◽

Hongbing Zhou ◽

Cheng Wu ◽

Zhi Chen

Keyword(s):

Surface Roughness ◽

Process Parameters ◽

Material Removal Rate ◽

Electrical Discharge ◽

Material Removal ◽

Electrical Discharge Machining ◽

Removal Rate ◽

High Volume ◽

Wire Electrical Discharge Machining ◽

Al Composite

With the properties of high specific strength, small thermal expansion and good abrasive resistance, the particle-reinforced aluminum matrix composite is widely used in the fields of aerospace, automobile and electronic communications, etc. However, the cutting performance of the particle-reinforced aluminum matrix composite is very poor due to severe tool wear and low machining efficiency. Wire electrical discharge machining has been proven to be a good machining method for conductive material with any hardness. Even so, the high-volume SiCp/Al content composite is still a difficult-to-machine material in wire electrical discharge machining due to the influence of insulative the SiC particle. The goal of this paper is to analyze the machining characteristics and find the optimal process parameters for the high-volume content (65 vol.%) SiCp/Al composite in wire electrical discharge machining. Experimental results show that the material removal method of the SiCp/Al composite includes sublimating, decomposing and particle shedding. The material removal rate is found to increase with the increasing pulse-on time, first increasing and then decreasing with the increasing pulse-off time, servo voltage, wire feed and wire tension. Pulse-on time and servo voltage are the dominant factors for surface roughness. In addition, the multi-objective optimization method of the nondominated neighbor immune algorithm is presented to optimize the process parameters for a fast material removal rate and low surface roughness. The optimized process parameters can increase the material removal rate by 34% and reduce the surface roughness by 6%. Furthermore, the effectiveness of the Pareto optimal solution is proven by the verified experiment.

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