Influence of the Pulse Duration onto the Material Removal Rate and Machining Quality for Different Types of Steel

The small hole EDM is one main method of micro holes machining and applied very widely. But it’s machining efficiency is low and machining stability is bad, which is more obvious because of chip-ejection difficulty when the ratio of length to diameter is rather large. Secondary discharge caused by chip-ejection difficulty not only makes the material removal rate reduce, but also causes geometric tolerance and affects product performance. Based on dispersion mechanism study of the water dispersant, the influence of the water dispersant is analyzed to chip-ejection, material removal rate and machining quality of the high-speed small-hole EDM. By contrasting the machining effect on using tap water with disperser dielectric liquid during electric spark small hole machining, adding the certain proportion disperser in water-based dielectric liquid may increase the material removal rate, decrease the tool wear rate, improve the effective impulse numbers, obviously reduce the second discharge number, and the taper of tool electrode and hole becomes small, so the hole machining quality enhances.

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Experimental Study on Submersed Gas-Jetting EDM

ASME 2008 International Manufacturing Science and Engineering Conference, Volume 1 ◽

10.1115/msec_icmp2008-72111 ◽

2008 ◽

Author(s):

X. M. Kang ◽

W. S. Zhao ◽

C. J. Tang ◽

L. S. Ding

Keyword(s):

Experimental Study ◽

High Pressure ◽

Pulse Duration ◽

Material Removal Rate ◽

Material Removal ◽

Removal Rate ◽

Dielectric Medium ◽

New Method ◽

Electrode Wear ◽

Tubular Electrode

A new method called submersed gas-jetting EDM was proposed, in which the high-pressure gas working as the dielectric medium, is blown throughout the inner hole of a tubular electrode, and machining liquid around the gas plays significant roles of helping cooling and debris evacuation but doesn’t involve in the discharge directly. Experiments were conducted to investigate the influence of polarity, pulse duration, peak current, gas pressure and different gas/machining liquid combination. The comparison of submersed gas-jetting EDM and dry EDM indicated that this new method revealed higher material removal rate (MRR), better surface quality and equivalently minute electrode wear.

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Experimental Study on Dry WEDM Finishing

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.455.190 ◽

2010 ◽

Vol 455 ◽

pp. 190-193 ◽

Cited By ~ 1

Author(s):

Tong Wang ◽

Feng Qiu ◽

C.Q. Wang ◽

G.Z. Zhang ◽

Xiao Cun Xu

Keyword(s):

Experimental Study ◽

Surface Roughness ◽

Pulse Duration ◽

Material Removal Rate ◽

Material Removal ◽

High Speed ◽

Removal Rate ◽

Cutting Speed ◽

Machining Parameters ◽

Dry Wedm

Comparing with conventional WEDM in emulsion, dry finishing of high-speed WEDM (HS-WEDM) has advantages such as higher material removal rate, better surface roughness and straightness. Authors have presented a new procedure as gas-liquid combined multiple cut, in which roughing is processed in dielectric liquid, and semi-finishing is in liquid or gas, while finishing is in gas. For better understanding the effect of machining parameters on surface roughness and cutting speed in dry finishing, a L25(56) Design was implemented. The analysis of variance shows that the effect of pulse duration on surface roughness is of high significance, and peak current is of significance respectively, and the effect of no load worktable feed on cutting speed is high significant.

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An Orthogonal Experimental Study of WEDM-HS of Particle-Reinforced 6061 Al Matrix Composites with 20-Vol% Al2O3

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.563.21 ◽

2014 ◽

Vol 563 ◽

pp. 21-24 ◽

Cited By ~ 1

Author(s):

Jiang Wen Liu ◽

Yong Zhong Wu

Keyword(s):

Pulse Duration ◽

Material Removal Rate ◽

Duty Cycle ◽

Material Removal ◽

Removal Rate ◽

Machining Parameters ◽

Matrix Composites ◽

Electro Discharge Machining ◽

Al Matrix Composites ◽

Al Matrix

An investigation has been made into the machining feasibility when wire electro-discharge machining with an extremely high travelling speed of wire electrode (WEDM-HS) has been employed to process particle-reinforced 6061 Al matrix composites with 20-vol% Al2O3 (20ALO). And in this study, for the water based emulsion is used as working liquid, there exists an electrochemical effect. And thus, the EDM spark can operate under a relatively large spark gap size condition, and this would be helpful for the removal of the loosen particles and the machined debris. In this study, the material removal rate (MRR) has been examined. Since there are many factors that can influence the MRR during the wire electro-discharge machining process, in order to determine which factor has the most significant effect on the MRR and to obtain the optimal machining parameters, the relative importance of the various machining parameters on material removal rate was analysed by employing an orthogonal design. The results of the orthogonal analysis show that to obtain a high MRR for WEDM-HS machining of 20ALO materials, the duty cycle has the most significant effect on the MRR among current, pulse duration and duty cycle. And the impact of significance for the different factors follows the sequence of duty cycle > current > pulse duration. And under the experiment condition of this study, a duty cycle of 1:4, a current of 5A and a pulse duration of 32μs is the best arrangement for the MRR.

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An Orthogonal Experimental Analysis of WEDM-HS of Al2O3 Particle-Reinforced Aluminum Alloy 6061 with 10-Vol% Al2O3

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.910.61 ◽

2014 ◽

Vol 910 ◽

pp. 61-64 ◽

Cited By ~ 2

Author(s):

Jiang Wen Liu ◽

Yong Zhong Wu

Keyword(s):

Aluminum Alloy ◽

Pulse Duration ◽

Material Removal Rate ◽

Duty Cycle ◽

Experimental Analysis ◽

Material Removal ◽

Removal Rate ◽

Machining Parameters ◽

Aluminum Alloy 6061 ◽

Alloy 6061

In wire electro-discharge machining with an extremely high travelling speed of wire electrode (WEDM-HS), the emulsion is used as working liquid. Because there exists a functional electrolyte, the EDM spark can operate under a relatively large spark gap size condition, and this would facilitate the removal of machined debris. An investigation has been made into the machining feasibility when WEDM-HS has been employed to process Al2O3particle reinforced aluminum alloy 6061 with 10-vol% Al2O3(10ALO). And the material removal rate (MRR) has been examined in this study. Since there are many factors that can influence the MRR in the WEDM-HS process, in order to determine which is the most important factor and to optimize the machining parameters, the relative importance of the various machining parameters on material removal rate was established by utilizing an orthogonal experimental analysis. The results of the analysis suggest that to achieve a high MRR for particulate reinforced aluminum 6061 with 10-vol% Al2O3, the duty cycle is the most influential factor among current, pulse duration and duty cycle. And the impact of the different factors follows the sequence of duty cycle > current > pulse duration.

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High Performance in EDM Machining of AISI D2 Hardened Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.500.259 ◽

2012 ◽

Vol 500 ◽

pp. 259-265 ◽

Cited By ~ 3

Author(s):

Faizul Ezmat Abdul Hamid ◽

Mohd Amri Lajis

Keyword(s):

Pulse Duration ◽

Material Removal Rate ◽

Electrical Discharge ◽

Material Removal ◽

High Performance ◽

Electrical Discharge Machining ◽

Removal Rate ◽

Hardened Steel ◽

Peak Current ◽

Aisi D2

In this paper an attempt has been made to investigate the performance of an electrode made through powder metallurgy (PM) of copper tungsten during electrical discharge machining (EDM). Experimental results are presented on electrical discharge machining of AISI D2 hardened steel in kerosene with a copper tungsten (Cu35% - W65%) tool electrode made through PM method with a constant duty factor of 80%. In term of high performance EDM process, higher peak current (>20A) and pulse duration (>400µs) with a high machining efficiency were used. Experimental results have shown that machining at a peak current of 40A and pulse duration of 400µs yields the highest material removal rate (MRR) whereas machining at a peak current of 20A and pulse duration of 400µs yields the lowest tool wear rate (TWR). The lowest surface roughness appears at the lowest material removal rate which is at a peak current of 20A and pulse duration of 600µs. The optimum machining performance can be performed by the combination of pulse duration and peak current at 600µs and 40A respectively.

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Effects of Pulse Duration and Current on EDM Process of Allegheny Ludlum D2 Tool Steel

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.315.369 ◽

2013 ◽

Vol 315 ◽

pp. 369-373

Author(s):

S. Sulaiman ◽

A.A. Khan ◽

M.A. Razak ◽

M.R. Ibrahim ◽

M.S. Yusof

Keyword(s):

Surface Roughness ◽

Wear Rate ◽

Pulse Duration ◽

Tool Steel ◽

Material Removal Rate ◽

Material Removal ◽

Removal Rate ◽

Electrode Wear ◽

Machining Parameters ◽

Edm Process

The purpose of this paper is to study the effect of current on performance of EDM process of Allegheny Ludlum D2 Tool Steel (UNS T30402). The effect of varying the machining parameters on the machining responses such as material removal rate (MRR), electrode wear rate (EWR), and surface roughness (Ra) have been investigated. In this study, circular shape of copper was used as an electrode with surface area of 100mm². The experiments were repeated for three different values of pulse duration (100µs, 200µs and 400µs) with combination of three different values of discharge current (12A, 16A and 24A). It was found that the pulse duration and current give significant effect on MRR, EWR and Ra. An increase in the pulse durations causes an increase in the MRR and Ra, but a decrease in the EWR. Meanwhile, the effect of currents on EDM performance shows that the increasing currents led to an increase in the MRR, EWR and Ra.

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