EDM deposition process is the power source of high energy stored in the metal electrode and the base material between the instantaneous release of high-frequency, through the electrode material and the base material of the gas ionisation between the formation of a number of micro-arc channels, so that the surface of the base material to produce instantaneous high-temperature micro-area, electrode material in the microelectrical field of the action of the fusion welded to the base material, the formation of the metallurgical bond. EDM process is a micro-area of repeated instantaneous high temperature – cooling process, it is different from traditional welding, solid basically no high temperature rise, and therefore will not produce stress, deformation and other phenomena.