Edm, used in the machinery industry, is an abbreviation of the initials of electrical discharge machining. It is a chip removal technique by eroding with the control of the spark formed as a result of electrical discharge. Looking at its history; the electrical discharge technique discovered by a British scientist named Joseph Priestley in the 1770s, laid the first foundations of EDM in 1943 with the realization of spark control. Two Soviet scientists named Boris Lazarenko and Natalya Lazarenko pioneered this. They immersed a conductive electrode into a non-conductive dielectric fluid and gave electric current to this electrode. The Lazarenkos succeeded in jumping the spark formed in the electrode to a conductive metal and the erosion process in a controlled manner. At this point, I would like to mention an example given by a speaker at an EDM techniques seminar I attended abroad years ago, which stuck in my mind. He explained erosion with electricity as follows:

"Imagine lightning striking a long electric pole standing right in front of you in rainy weather with heavy lightning. The clouds direct all their electricity to a metal with a different electric charge at the nearest distance to discharge the positive energy on them. During this discharge, the negatively charged metal pole also tends to discharge all its potential load to the ground. And when you go near the pole, you see that a hole has formed in the area where the pole comes into contact with the ground. Even though the air is not conductive, when the distance between the clouds and the ground or the nearest metal reaches a certain low value, suddenly the air plays a conductive role and lightning strike, which we call spark jumping, occurs. The EDM logic works in the same way."

Although pure water or dielectric fluid is not conductive, when the electrode charged with a specific and controllable energy is brought closer to the surface to be eroded, it becomes conductive and carries the spark to the metal, ensuring the formation of deformation. In EDM machines, this processing technique takes place depending on many parameters. There are numerous edm parameters that need to be controlled, such as approach distance, speed, the type of electrode used, the type of metal to be eroded, the related electrical power, and ampere values. EDM machines are divided into two categories: Wire EDM and Sinker EDM machines (Sink edm machine).

Under the edm erosion machines category, there are listings and prices for pre-owned and new cnc edm machine sellers, and second hand for sale edm erosion machines from owner.