Erosion (from Lat. Erosio – attack) – the process of destruction of the surface under the impact of shocks, friction, electrical discharges etc. Spark erosion is to change shape, geometric dimensions, the roughness surface under the action of electric discharges. The method was first proposed by Soviet scientists B. Lazarenko in the early 30-ies of XX century and became effective alternative to conventional machining, reducing the cost of manufacturing. Unfortunately, this method of treatment of products currently in Russia deserve forgotten, despite the diversity of its capabilities and worldwide recognition.
The method allows the following treatments: cutting hard metals Precision Milling, Grinding, Lapping Other methods used in the manufacture of molds, dies, extrusion dies, patterns, parts of a complex curvilinear Profile, tools, and various cutting tools, dental supplies. The essence of the method is electrical discharge machining. Machining of the workpiece and tool electrodes are (part-plus Machining tools – minus), placed in a special working conductive liquid. With the passage of an electric discharge between the electrodes of an arc and in places it is of local heating and subsequent evaporation of the metal particles with the formation of local depressions. The size of pits depends on the density of electrical energy. To get arcs that can destroy the surface workpiece using a pulse generator.
Almost all of the currently available tools, designed for ESS can be divided into several groups: broaching machines – the main technological problem of these machines is making the holes. The control system of the machine actually runs only one axis – Z. On the axes X and Y are installed optical ruler. On it by moving the electrode in a container with kerosene. The machine is mostly used for finishing products. Duplicating Machines Saddle – more complicated, "fancy" Saddle modification. They are used for the manufacture and finishing finishing details complex shapes, such as dies, molds, handling of the Deaf, cutting, angular grooves, burning internal threads in remote places. Have a high capacity for arable products. In addition, They established a system with CNC control pulse generator, and Items of the machine in the X and Y. Wire-cut-out machines – the main technological challenge of making it part of the hard tooling steel sections which are uncomfortable to handle the milling. Wire EDM can be used in the manufacture of products with a presence on the surfaces of acute internal corners, small radii or when machined parts or depth electrodes presents difficulties for milling. The main processing element – special (Molybdenum) wire, in irregularly wound bobbin and fed continuously in accordance with wear a special die. The control system is more complicated because of the need for control 5 axes: X, Y, Z, as well as U and V – to move the upper die with respect to the bottom. These shifts are necessary for the slope wire.