Multi-characteristic optimization of WEDM for Ti-6Al-4V by applying grey relational investigation during profile machining

Abstract

This research work presents multi-quality features optimization while wire electrical discharge machining (WEDM) of Ti-6Al-4V. Taguchi's L27 orthogonal arrangement is applied to inspect the outcome of governing variables such as pulse-on period, pulse-off interval, discharge voltage, discharge current, wire feed speed and cable tension on the kerf width, material removal rate (MRR), the surface roughness (SR) and overcut during intricate profile manufacturing on Ti-6Al-4V. To optimize all six governing variables, the grey relational investigation (GRI) is applied. The grey relational score is used as a multi-quality unique index (MQUI). From the experimental results the optimal configuration of governing variables obtained is pulse-on period 110 µs, pulse-off interval 55 µs, discharge voltage 40 volts, discharge current 170 Amp., wire feed speed 3 m/min and cable tension 8 gram. ANOVA analysis indicates that pulse-on period is an essential variable concerning the quality outputs. Results of confirmation trials show that the optimal governing variables improved the grey relational score (GRS) from 0.9048 to 0.9226 for the multiple responses. SEM analysis of machined parts shows that at high values of pulse on period and discharge current, deep craters, globules of debris, voids, and micro cracks are formed on the cut surface thus deteriorating the surface finish.Keywords: WEDM; Ti-6Al-4V; Taguchi method; grey relational investigation; grey relational score; profile machining; SEM analysis. S.A.Sonawane et. al / Journal of Mechanical Engineering and Sciences 13(4) 2019 6059-6087 6060 and non-electrical parameters affecting the quality measures namely metal removal rate (MRR), surface finish, surface integrity, and dimensional accuracy. WEDM technology has been widely used in conductive material machining mainly for the production of mold, dies, medical and dental instrumentation, graphite electrodes, parts of automotive and aerospace industries [1]. The process output is a combination of electrodynamic, electromagnetic, thermal dynamic and hydrodynamic actions.Jose and Shunmugum [2] studied the effect of WEDM process factors on surface finish and white layer thickness while machining Ti-6Al-4V. They found that the thickness of the white layer increases with an increase in the pulse on duration. Micro cracks were also observed in the white layer. Pasam et al.[3] studied surface finish characteristic during WEDM of Titanium grade-5. They considered different process factors such as ignition pulse current, injection pressure, short pulse duration, servo reference voltage, the time between two pulses, wire speed, servo speed, and wire tension. A genetic algorithm was employed for the optimization of the surface finish. Jabbaripour et al.[4] carried out electrical discharge machining of Ti-6Al-4V to study the influence of pulse on time, pulse current and open circuit voltage on TWR, MRR and recast layer thickness, microhardness and surface topography of the machined surface. From the results of experiments, it was fo...

Multi-Independent Optimization while Turning of Inconel-600 alloy using Grey Interactive Exploration

“…A scheme for which the pertinent material is fully identified is a white arrangement, while a structure for which application data is fully strange is a "black" scheme. Some scheme between these boundaries is a grey method having miserable and inadequate statistics (Sonawane et al 2019). Grey interactive exploration is a normalized appraisal technique that effectively solves the complicated multi-performance characteristic optimization.…”

Multi-parametric optimization of Wire-EDM machining on artificially-aged al6061/b 4 c composite using RSM and grey relational analysis

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Optimization of material removal rate and surface characterization of wire electric discharge machined Ti-6Al-4V alloy by response surface method

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