Influence of input parameters on the electrical discharge machining of titanium alloy (TI-6AL-4V)

Electrical discharge machining (EDM) is a thermo-electrical process that can be conveniently utilized for generating complex shaped profiles on hard-to-machine conductive materials using metallic tool electrodes. In this work, composite tools made of copper-tungsten-boron carbide (Cu-W-B4C) manufactured by powder metallurgy (PM) route are used during machining of titanium alloy (Ti6Al4V). The effect of four input machining parameters viz. current, pulse-on-time, duty cycle and percentage of tungsten and boron carbide on material removal rate (MRR), tool wear rate (TWR) and surface roughness (Ra) is studied. A novel meta-heuristic approach such as simple optimization (SOPT) algorithm has been used for single and multi-objective optimization. The pareto-optimal solutions obtained by SOPT have been ranked by VIKOR method to find out the best suitable optimal solution. Analysis of experimental data suggests vital information for controlling the machining parameters to improve the machining performance.

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Evaluating Optimal Parameters for Machining Selective Laser Melting Titanium Alloy Using Wire Cut Electrical Discharge Machining

International Journal of Manufacturing Materials and Mechanical Engineering ◽

10.4018/ijmmme.2020070104 ◽

2020 ◽

Vol 10 (3) ◽

pp. 62-72

Author(s):

Ashwin Polishetty ◽

Guy Littlefair

Keyword(s):

Titanium Alloy ◽

Selective Laser Melting ◽

Electrical Discharge ◽

Metal Removal ◽

Electrical Discharge Machining ◽

Removal Rate ◽

Chemical Reactivity ◽

Laser Melting ◽

Machining Speed ◽

Wire Feed

Titanium is known for its poor machinability characteristics due to its low thermal conductivity and high chemical reactivity. This article explores the machinability characteristics of selective laser melting (SLM) titanium alloy Ti-6Al-4V using wire cut electrical discharge machining (WEDM). For titanium alloys, exploring non-traditional machining operation such as WEDM is critical for a material failure or success in a design application. The research is to study the effect of parameters such as servo voltage, pulse on/off, and machining speed with respect to wire tension and wire feed rate on machinability. The outputs under consideration for evaluating machinability are metal removal rate (MRR) and surface finish under minimal interruption due to wire snaps. The article concludes by identifying the optimal factors responsible to produce an efficient and accurate cut with a minimum downtime.

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Study on the improvement of the surface integrity and efficiency of electrical-discharge-machined TC4 titanium alloy via abrasive flow machining

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

10.1177/0954405420971097 ◽

2020 ◽

pp. 095440542097109

Author(s):

Ze Yu ◽

Dunwen Zuo ◽

Yuli Sun ◽

Guohua Li ◽

Xuemei Chen ◽

...

Keyword(s):

Surface Roughness ◽

Titanium Alloy ◽

Surface Quality ◽

Electrical Discharge ◽

Electrical Discharge Machining ◽

Small Hole ◽

Machining Process ◽

Machining Efficiency ◽

Abrasive Flow Machining ◽

Tc4 Titanium Alloy

To simultaneously optimize the surface quality and machining efficiency of the electrical discharge machining (EDM) processes used to produce titanium alloy quadrilateral group small hole parts, a combined “EDM + AFM” machining technology is proposed in this paper as an efficient and high-quality machining approach. In the proposed method, TC4 titanium alloy is first machined using the EDM process with graphite electrodes and the abrasive flow machining (AFM) process is then used to finish the machined surface. The effects of various electrical parameters on EDM-derived surface quality and improvements in EDM-derived quality under the application of AFM were assessed and, using the final surface roughness as a constraint condition, the effects of various combinations of EDM and “EDM + AFM” on efficiency were studied. The results revealed that the thickness and surface roughness of the superficial recast layer of the TC4 titanium alloy increase with both current and pulse width; in particular, increasing these parameters can increase the surface roughness by two to three grades. Following AFM, the alloy has a more uniform hardness distribution and the surface stress state changes from tensile to compressive stress, indicating that the combined “EDM + AFM” machining scheme can significantly enhance the surface quality of EDM-produced titanium alloy quadrilateral small group holes. The combined scheme achieves a balancing point beyond which increasing the roughness or the number of machining holes enhances either the machining efficiency or the machining surface quality. In the case of typical titanium alloy quadrilateral group small hole parts, the combined machining process can improve the finishing efficiency and total machining efficiency by 71.2% and 25.36%, respectively.

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Surfactant and graphite powder–assisted electrical discharge machining of titanium alloy

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

10.1177/0954405415579019 ◽

2016 ◽

Vol 231 (4) ◽

pp. 641-657 ◽

Cited By ~ 21

Author(s):

Murahari Kolli ◽

Adepu Kumar

Keyword(s):

Surface Roughness ◽

Titanium Alloy ◽

Electrical Discharge ◽

Material Removal ◽

Electrical Discharge Machining ◽

Removal Rate ◽

Graphite Powder ◽

Recast Layer ◽

Dielectric Fluid ◽

Recast Layer Thickness

Surfactant and graphite powder–assisted electrical discharge machining was proposed and experiments were performed on titanium alloy in this investigation. Analysis was carried out to observe changes in dielectric fluid behaviour, material removal rate, surface roughness, recast layer thickness, surface topography and energy-dispersive X-ray spectroscopy. It was found out that the addition of surfactant to dielectric fluid (electrical discharge machining oil + graphite powder) improved the material removal rate and surface roughness. It was noticed to have reduced the recast layer thickness and agglomeration of graphite and sediment particles. Biface material migrations between the electrode and the workpiece surface were identified, and migration behaviour was powerfully inhibited by the mixing of surfactant. Surfactant added into dielectric fluid played an important role in the discharge gap, which increased the conductivity, and suspended debris particles in dielectric fluid reduced the abnormal discharge conditions of the machine and improved the overall machining efficiency.

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Fundamental Study on Addition of Osteoconductivity to Titanium Alloy Surface by EDM

International Journal of Automation Technology ◽

10.20965/ijat.2017.p0869 ◽

2017 ◽

Vol 11 (6) ◽

pp. 869-877 ◽

Cited By ~ 2

Author(s):

Togo Shinonaga ◽

◽

Yuta Iida ◽

Ryota Toshimitsu ◽

Akira Okada

Keyword(s):

Rheumatoid Arthritis ◽

Titanium Alloy ◽

Bone Tissue ◽

Electrical Discharge ◽

Electrical Discharge Machining ◽

Alloy Surface ◽

Artificial Joint ◽

Joint Function ◽

Fundamental Study ◽

Joint Shape

In recent years, one common cure for losses in joint function caused by osteoarthritis or rheumatoid arthritis is replacement with an artificial joint. For this reason, it is necessary to add osteoconductivity to artificial joint component surfaces that make contact with bone, thereby reducing the period of time necessary to fixate the bone tissue and the artificial joint component. With the intent of efficiently machining the joint shape by electrical discharge machining (EDM) and simultaneously formation of a surface with osteoconductivity, this study discusses the possibility of adding osteoconductivity to a titanium EDMed surface.

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Fuzzy Logic Control System for Micro-Hole Electrical Discharge Machining

ASME 2007 International Manufacturing Science and Engineering Conference ◽

10.1115/msec2007-31193 ◽

2007 ◽

Cited By ~ 2

Author(s):

Chen-Chun Kao ◽

Scott F. Miller ◽

Albert J. Shih

Keyword(s):

Fuzzy Logic ◽

Control System ◽

Ignition Delay ◽

Fuzzy Logic Control ◽

Electrical Discharge ◽

Electrical Discharge Machining ◽

Logic Control ◽

Input Parameters ◽

Micro Hole ◽

Adaptive Fuzzy Logic

An advanced micro-hole electrical discharge machining (EDM) system with the adaptive fuzzy logic control and precision piezoelectric stage is developed in this study. A high-speed EDM monitoring system is implemented to measure the gap voltage, current, and ignition delay time, which are used to derive three input parameters, the average gap voltage, deviation of spark ratio, and change of deviation of spark ratio, for the fuzzy logic control. Servo displacement and speed of the piezoelectric stage during each data acquisition cycle are real-time synthesized by the adaptive fuzzy logic controller. Effects of the single and multiple input parameters, ignition delay threshold value, and maximum servo displacement and speed on the EDM drilling process are experimentally studied. Design of experiments (DOE) is applied to investigate the correlation of fuzzy logic control parameters. The optimal EDM parameter values are searched via the genetic algorithm. The optimal search result is experimentally validated. The fuzzy logic EDM control system has demonstrated the efficiency and stability in micro-hole drilling by reducing the frequency of irregular discharges and the drilling time.

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Modelling and investigating the effect of input parameters on surface roughness in electrical discharge machining of CK45

Tehnicki vjesnik - Technical Gazette ◽

10.17559/tv-20141024224809 ◽

2016 ◽

Vol 23 (3) ◽

Keyword(s):

Surface Roughness ◽

Electrical Discharge ◽

Electrical Discharge Machining ◽

Input Parameters

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Modeling and Optimization of Wire Electrical Discharge Machining of Cold-Work Steal 2601

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.383-390.6695 ◽

2011 ◽

Vol 383-390 ◽

pp. 6695-6703 ◽

Cited By ~ 2

Author(s):

Abolfazl Golshan ◽

Soheil Gohari ◽

Ayob Amran

Keyword(s):

Electrical Discharge ◽

Electrical Discharge Machining ◽

Removal Rate ◽

Cold Work ◽

Open Circuit ◽

Experimental Result ◽

Wire Electrical Discharge Machining ◽

Machining Parameters ◽

Input Parameters ◽

Pulse Off Time

In this study, the appropriate input parameters for achieving minimum surface roughness and high material removal rate are selected for wire electrical discharge machining of cold-work steel 2601. Mathematical modeling acquired by experimental result analysis is used to find the relation between input parameters including electrical current, gap voltage, open-circuit voltage and pulse-off time and output parameters. Subsequently, with exploitation of variance analysis, importance and effective percentages of each parameter are studied. The combination of optimum machining parameters is acquired using the analysis of ratios of signal-to-noise. Finally, according to multiple-objective optimization, outputs acquired from Non-dominated Sorting Genetic Algorithm led in achieving appropriate models. The optimization results showed suggested method has a high performance in problem solving.

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