Electrochemical Discharge Grinding of Metal Matrix Composites Using Shaped Abrasive Tools Formed by Sintered Bronze/diamond

AbstractElectrochemical discharge machining (ECDM) is a well-known process for machining of particulate reinforced metal matrix composites (MMCs). However, ECDM process suffers several drawbacks such as the lower material removal rate (MRR), high risks of tool wear rate (TWR) and relatively poor surface quality, etc. This study proposes a kind of electrochemical discharge grinding machining (ECDGM) method which employs a special shaped tool electrode. During the process, not only the can the hybrid action of electrochemical dissolution, spark erosion, and abrasive grinding improve the performance of machining MMCs, but also the special shaped of the tool electrode can be used to discharge the machined debris. And thus a higher machining efficiency and lower TWR can be obtained. The performance of developed process was conducted on machining of SiC particulate reinforced aluminum workpiece. The role of peak curre+nt, pulse duration, duty cycle, rotary speed and abrasive grit size has been investigated on MMR and TWR using the nonabrasive round electrode, abrasive round electrode, and abrasive shaped electrode respectively. The experimental results showed that using the shaped abrasive electrode for machining MMCs can achieve a higher MRR and lower TWR, as compared to the non-abrasive round electrode, abrasive round electrode. Besides, the orthogonal method was employed to analyze the relative importance of the machining parameters on MRR and TWR, it has been observed that MRR is affected by the processing parameters following the order of rotary speed > peak current > duty cycle > pulse duration, and TWR is following the order of peak current > duty cycle > pulse duration > rotary speed.

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Electrical Discharge Machining of Metal Matrix Composites with a High Speed Non-Round Electrode

Advanced Composites Letters ◽

10.1177/096369351602500603 ◽

2016 ◽

Vol 25 (6) ◽

pp. 096369351602500 ◽

Cited By ~ 1

Author(s):

J.W. Liu ◽

Y.J. Xiao ◽

Z.N. Guo ◽

S.J. Wang ◽

T.M. Yue ◽

...

Keyword(s):

Metal Matrix Composites ◽

Pulse Duration ◽

Duty Cycle ◽

Metal Matrix ◽

Electrical Discharge ◽

Electrical Discharge Machining ◽

Rotation Speed ◽

Tool Electrode ◽

Matrix Composites ◽

Electrode Rotation

An electrical discharge machining process with a high electrode rotation speed (EDM-HS) has been developed to solve the problems of the conventional EDM process in machining metal matrix composites (MMCs). The EDM-HS process employs a non-round tool electrode. The experiment results showed that the materials removal rate (MRR) of the workpiece can be improved significantly by employing a non-round tool electrode. The relationship between the pulse duration, machining current, duty cycle, the rotation speed of the tool electrode and the MRR has been studied respectively. And the machining mechanism of this EDM-HS process has been analyzed both theoretically and experimentally. The results showed that the non-round electrode can enlarge the machining gap and with a high electrode rotation speed, the machined debris can be discharge out of the machining area effectively and hence a stable machining condition can be obtained. As a result, a higher MRR can be achieved. Moreover, an orthogonal analysis has been utilized to study the relative importance of the machining parameters on MRR. It was found that to obtain the highest MRR, the electrode rotation speed was the most influential factor among the duty cycle, machining current, pulse duration and electrode rotation speed. This outcome supports that it is feasible to use this novel method to machining particulate reinforced MMCs, where a higher MRR can be achieved.

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Single Pulse Study of Electrochemical Discharge Machining of Metal Matrix Composites

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.200.536 ◽

2012 ◽

Vol 200 ◽

pp. 536-539 ◽

Cited By ~ 4

Author(s):

Jiang Wen Liu ◽

Guang Xue Chen ◽

Tai Man Yue ◽

Zhong Ning Guo

Keyword(s):

Metal Matrix Composites ◽

Metal Matrix ◽

Electrical Discharge Machining ◽

Single Pulse ◽

Matrix Composites ◽

Electrochemical Discharge Machining ◽

Electrochemical Discharge ◽

Crater Volume ◽

Particulate Reinforced ◽

Volume Difference

Single pulse experiments were conducted to study electrochemical discharge machining (ECDM) of particulate reinforced metal matrix composites (MMCs) which are widely used in the packaging industry. This article reports the first phase of this study with an emphasis on the effects of pulse current on crater volume. The results showed that all the ECDM craters have a circular shape surrounded by a rim of re-solidified material. This indicates that ECDM craters were created by arc effect. The craters produced by both electrical discharge machining (EDM) and ECDM increased in volume with increasing peak current. However, within the range of currents studied, the craters formed by ECDM were always smaller than those produced by EDM alone under the same current. Moreover, the crater volume difference between EDM and ECDM did not change considerably with increasing current. This is considered to be due to an increase in ECDM current mainly enhances the arc energy and has little effect on the ECM action. Furthermore, the experiment results showed that the efficiency of the arc action in ECDM is reduced when the percent of reinforcement phase is increased.

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