Tuesday June 30, 2009 - In 1770, English phsicist Joseph Priestley noted in his research the erosive effect of electrical discharges on various metals.

Based off of Priestley's earlier research, during a separate study to eliminate the erosive effect on electrical contacts, the Soviet researchers B.R. and N.I Lazarenko had the idea of exploiting the destructive effects of an electrical discharge and develop a controlled process for machining of metals.

In 1943, they developed a spark machining process, thus called because of the fact that a succession of sparks (electrical discharges) took place between two electrical conductors immersed in a dielectric fluid.

The discharge generator effect then used, known as the Lazarenko Circuit, was used for a long time in the construction of generators of EDM machines.
Improved, this type of generator is still used today for some applications.

The spectacular changes in EDM are due also to the perseverance of several other researchers who contributed to the highlighting the fundamental characteristics of this machining method and to obtaining, at present, the best possible advantages from this process.

In 1952, the manufacturer Charmilles, because interested in spark erosion machining, created the first machine using this machining process was presented for the first time at the European Machine Tool Exhibition in Milan in 1955.
Numerical control and feedback loops with ultra fast servos were added in the 1970's.
Today, full 3-D CAD/CAMS feed the controls of the machines with code generated to control path and spark characteristics.