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CHAPTER 1
INTRODUCTION
1.1 Background
Today’s society could not exist without modern manufacturing and production techniques. In fact, one of the indicators used to measure a country’s
economic strength is its manufacturing and production capability. Mass production with interchangeable parts is vital to our standard living. One cannot even imagine
the difficulty involved in making an automobile, a modern tractor used on a farm, or a commercial aircraft if all the parts had to be made by hand. Without modern
manufacturing methods, we could not even the present population.
Electrical Discharge Machining EDM is a non-traditional manufacturing process based on removing material from a part means of a series of repeated
electrical discharges between a tool, called electrode, and the part being machined in the presence of a dielectric fluid. There are many of parameters that must to indicate
such as surface roughness, semi-finish machining and finishing. But in this research, I will come out the patent debris upon the work piece based on the current signal.
EDM is using electric sparks to remove certain material from the metal. An electrode is lowered into dielectric fluid where the piece of metal being cut is
submerged. The electrode can be made of carbon, brass, or bronze. Brass and bronze are the better material to use for electrodes because unlike carbon, they won’t
break. The electrode is used to connect to the metal to conduct a large enough electric potential to create a spark that would remove material from the metal. The
electrode is constantly fed down to the work piece at a certain rate to maintain a constant gap. Plus, a hose that discharge dielectric field is constantly used after a cut
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frequency which is proportional to gap voltage and the discharge current. If either one of those parameter are increased, the removal rate of metal increases but also the
roughness of the job. EDM is a nontraditional machining process since it does not remove material with a cutting tool. It is used on materials that are extremely hard or
and brittle, the features to be made are extremely complex or small, and also the temperature rise or stress in the work piece can not be tolerated.
There is a voltage gap between the electrode and the work piece that form the spark vaporizes minute particles of the work piece material, which is then
washed out from the gap by the continuously flushing dielectric fluid. The two main types of the EDM are Ram and Wire cutting. EDM is a diverse process that
produces products ranging from tiny electric connectors, medical parts, and automatic stamping dies and aircraft body panels. EDM has replaced much of the
machining, grinding steps needed in die making which represents the largest single use of EDM. Die component cut with EDM can often be made in a single piece no
matter how complex the internal form. The single piece die are always stronger than those made of segments. Die cut are from hardened steel, heat-treated steel, carbide.
Other materials that can be EDM are polycrystalline diamond, titanium, hot rolled and cold rolled steel, copper, brass and high temperature alloys.
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1.2 Objectives
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