Electrode wear pattern during EDM milling of Inconel 718

In this work, the electrode wear rate (EWR) and electrode surface characteristic of copper electrode when EDM of Nickel Based Super Alloy, Inconel 718 at higher peak current and pulse duration were analyzed. Experiments were conducted using Inconel 718 as a work piece and copper as an electrode with a kerosene dielectric under different peak currents and pulse durations. Peak current, Ip within a range of 20A to 40A and pulse duration (or pulse on-time), ton within a range of 200μs to 400μs are selected as the main parameters. In this study, EWR were measured using digital weight balance (accuracy 0.01mg) and by using Scanning Electron Microscope (SEM), the surface texture of the electrode in order to evaluate the material deposited on the electrode surface. The results have shown that machining at a lowest peak current of 20A and highest pulse duration of 400μs yields the lowest electrode wear rate (EWR) of -0.01mm3/min. The pulse duration is significantly affecting the EWR. It also revealed that, the deposited of carbon and work piece material is occurred on the electrode surface for all machining conditions.

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EDM PROCESS PARAMETER OPTIMIZATION FOR EFFICIENT MACHINING OF INCONEL-718

Facta Universitatis Series Mechanical Engineering ◽

10.22190/fume200406035s ◽

2020 ◽

Vol 18 (3) ◽

pp. 473

Author(s):

Ankit Singh ◽

Ranjan Kumar Ghadai ◽

Kanak Kalita ◽

Prasenjit Chatterjee ◽

Dragan Pamučar

Keyword(s):

Wear Rate ◽

Inconel 718 ◽

Removal Rate ◽

Subjective Evaluation ◽

Fluid Pressure ◽

Objective Evaluation ◽

Dielectric Fluid ◽

Electrode Wear ◽

Machining Performance ◽

Edm Process

In the present work, multi-response optimization of electro-discharge machining (EDM) process is carried out based on an experimental analysis of machining superalloy Inconel-718. The study aims at optimizing and determining an optimal set of process variables, namely discharge current (), pulse-on duration () and dielectric fluid-pressure () for achieving optimal machining performance in EDM. Nine independent experiments based on L9 orthogonal array are carried out by using tungsten as the electrode. The productivity performance of the EDM process is measured in terms of material removal rate (MRR) and its cost parameter is measured in terms of tool wear rate (TWR) and electrode wear rate (EWR). The TOPSIS is used in conjunction with five different criterion weight allocation strategies— (namely, mean weight (MW), standard deviation (SDV), entropy, analytic hierarchy process (AHP) and Fuzzy). While MW, SDV and entropy are based on the objective evaluation of the decision-maker (DM), the AHP can model the DM’s subjective evaluation. On the other hand, the uncertainty in the DM’s evaluation is analyzed by using the fuzzy weighing approach.

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Optimization of machining characteristics for EDM of different nickel-based alloys by embodying of fuzzy, grey relational and Taguchi technique

World Journal of Engineering ◽

10.1108/wje-07-2020-0262 ◽

2020 ◽

Vol 18 (1) ◽

pp. 23-36

Author(s):

Sahil Sharma ◽

Umesh Kumar Vates ◽

Amit Bansal

Keyword(s):

Inconel 718 ◽

Machining Process ◽

Simultaneous Optimization ◽

Inconel 625 ◽

Electrode Wear ◽

Peak Current ◽

Content Type ◽

Grey Relational ◽

Pulse On Time ◽

Machining Characteristics

Purpose In the current exploration, the machinability of three different nickel-based super-alloy materials (Inconel 625, Inconel 718 and Nimonic 90) was experimentally investigated by using a die-sinking electrical discharge machining (EDM). The effect of changing important input process parameters such as pulse on time (Ton), off time (Toff), peak current (Ip) and tool rotation (TR) was investigated to get optimum machining characteristics such as material removal rate, roughness, electrode wear rate and overcut. Design/methodology/approach Experimentation has been performed by using Taguchi L9 orthogonal design. An integrated route of fuzzy and grey relational analysis approach with Taguchi’s philosophy has been intended for the simultaneous optimization of machining output parameters. Findings The most approbatory factors for machining setting have been attained as: (Ton = 100 µs, Toff = 25 µs, Ip = 14 A, TR = 725 rpm) for machining of Inconel 625 and Inconel 718; and (Ton = 100 µs, Toff = 75 µs, Ip = 14 A, TR = 925 rpm) for machining of the Nimonic 90 material. Peak current has been observed as an overall influencing factor to achieve better machining process. Microstructural study through SEM has also been carried out to figure out the surface morphology for the EDMed Ni-based super alloys. Originality/value The proposed machining variables and methodology has never been presented for Nimonic 90 alloy on die-sinking EDM.

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The Nature of Delta Phase Precipitation in Inconel 718

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055916 ◽

1982 ◽

Vol 40 ◽

pp. 724-725

Author(s):

L. S. Lin ◽

C. C. Law

Keyword(s):

Inconel 718 ◽

Base Alloy ◽

High Strength ◽

Physical Metallurgy ◽

Nickel Base Alloy ◽

Phase Precipitation ◽

Weight Percentage ◽

Delta Phase ◽

The Subject ◽

Nickel Base

Inconel 718, a precipitation hardenable nickel-base alloy, is a versatile high strength, weldable wrought alloy that is used in the gas turbine industry for components operated at temperatures up to about 1300°F. The nominal chemical composition is 0.6A1-0.9Ti-19.OCr-18.0Fe-3Mo-5.2(Cb + Ta)- 0.1C with the balance Ni (in weight percentage). The physical metallurgy of IN 718 has been the subject of a number of investigations and it is now established that hardening is due, primarily, to the formation of metastable, disc-shaped γ" an ordered body-centered tetragonal structure (DO2 2 type superlattice).

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