erode certain parts of work piece to change them to the final desired
shapes.Now a days maching has been classified in two types:
Conventional machining or Traditional
Non conventional or Non-traditional
Conventional machining or traditional
machining process can be defined as a process using mechanical (motion) energy
for example it requires a tool which is harder than the work piece to be machined.
This tool should be dispersed in the work piece to a certain depth, Moreover, a
relative motion between the workipece and tool is responsible for developing
the required shape.
machining utilizes the other forms of energy. The term Non conventional
machining refers to material removal in terms of chips or debris having of
small dimensions/size in micro levels. V.K.Jain (2002) , P.C.Pandey and
H.S.Shan (1997).Non-conventional machining processes are classified according
to the machining action which helps in removal of material from, the work piece.
Non Conventional Machining have
various industrial applications particularly in aerospace, medical treatment,
electronics, military, computer and micro mechanics, manufacturing industries.
DISCHARGE MACHING (EDM)
phenomenon of erosion of metals by electrical spark was first noticed by Joseph
Priestly in 1878 but this was not used for machining of metals until 1930s.
Controlled machining of metals by electric sparks was done firstly by Lazarenko
in Russia in 1944.
of the most widely used Non-conventional machining processes in industry is Electro Discharge Machining (EDM) is an
electro-thermal non-traditional machining Process, where electrical energy is
used to generate an electrical spark and material removal mainly occurs due to the
thermal energy of the spark is mainly used to machine difficult-to-machine
materials and high strength, temperature resistant alloys. EDM can be used to
machine difficult geometries in small batches or even on the job – shop basis.
Work material to be machined by EDM has to be electrically conductive.