OCTOBER 19-20, 2012 - YMCA University of Science & Technology

Proceedings of the National Conference on
Trends and Advances in Mechanical Engineering,
YMCA University of Science & Technology, Faridabad, Haryana, Oct 19-20, 2012
Electrical Discharge Machining of Aluminum Metal Matrix Composites- A
Review
Bhaskar Chandra Kandpal 1*, Jatinder kumar 2 , Hari Singh 3
1 Assistant professor, Mechanical engineering, Inderprastha Engineering College ,Ghaziabad, U.P.
2 Assistant professor,Mechanical engineering,National Institute of Technology,Kurukshetra, Haryana
3 Associate professor,Mechanical engineering,National Institute of Technology,Kurukshetra, Haryana
1* E-mail:kandpalbhaskar2000@gmail.com, Ph. No – 9717508244
Abstract
Electrical discharge machining (EDM) is the process of machining electrically conductive materials by using
precisely controlled sparks that occur between an electrode and a work piece in the presence of a dielectric
fluid. Aluminium metal matrix composites (AMMCs) refer to the class of light weight high performance
aluminum ceramic material systems. The reinforcement in AMMCs could be in the form of continuous /
discontinuous fibers, whiskers or particulates, in volume fractions ranging from a few percent to 70%. These
materials are extensively used in industry. Greater hardness and reinforcement makes it difficult to machine
using traditional techniques, which has impeded the development of AMMCs. These materials can be machined
by many non traditional methods like water jet and laser cutting but these processes are limited to linear cutting
only. This paper presents a review of research work related to electrical discharge machining process of
aluminium metal matrix composites (AMMCs).
Keywords: EDM (Electrical discharge machining), aluminium metal matrix composite (AMMC).
1. Introduction
Electric discharge machining (EDM), sometimes colloquially also referred to as spark machining, spark eroding,
burning, die sinking or wire erosion, is a manufacturing process whereby a desired shape is obtained using
electrical discharges (sparks).
1.1 Working principle of electrical discharge machining
The working principle of EDM process as shown in figure 1 is based on the thermoelectric energy. This energy
is created between a workpiece and an electrode submerged in a dielectric fluid with the passage of electric
current. The workpiece and the electrode are separated by a specific small gap called spark gap. Pulsed arc
discharges occur in this gap filled with an insulating medium, preferably a dielectric liquid like hydrocarbon oil
or de- ionized water. Electrical discharge machining is a machining method primarily used for hard metals or
those that would be very difficult to machine with traditional techniques.
Figure 1: Schematic Diagram of EDM Process
2. Aluminium metal matrix composite materials
Aluminium metal matrix composite (AMMCs) refer to the class of light weight high performance aluminium
centric material systems. The reinforcement in AMMCs could be in the form of continuous / discontinuous fibres,
whisker or particulates, in volume fractions ranging from a few percent to 70%. Properties of AMMCs can be
tailored to the demands of different industrial applications by suitable combination of matrix, reinforcement and
processing routes. There are various types of AMMCs like Al/ SiC , Al/ Al 2 O 3 , Al. Ti C, etc. which are
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