Principles of Wire EDM

1. The principle of CNC wire cutting is as follows

The workpiece is connected to the positive electrode of the high-frequency pulse power supply, and the electrode wire is connected to the negative electrode, that is, positive processing is adopted. The working fluid medium is poured between the workpieces. When the high-frequency pulse power supply is energized, with the ionization and breakdown of the working fluid, a discharge channel is formed. The electrons rush to the positive electrode at a high speed, and the positive ions rush to the negative electrode. Then the electric energy is converted into kinetic energy, the collision between particles and the particles and electrode materials The collision of kinetic energy turns into heat energy. In the discharge channel, the surfaces of the positive electrode and the negative electrode respectively become instantaneous heat sources, reaching a high temperature, which causes the working fluid medium to vaporize, thermally crack, and melt, boil, and vaporize the metal material. Under the combined effects of thermal expansion, local micro-explosion, electric power, and fluid power, the eroded metal particles are thrown out of the discharge area along with the movement of the electrode wire and the washing of the working fluid, thus forming pits on the metal surface. During the interval between pulses, the working fluid medium deionizes, and the charged particles in the discharge channel recombine into neutral particles, which restores the insulation of the working fluid. Because the machining process is continuous, the stepping motor is controlled by the control system to make the worktable move in two coordinate directions on the horizontal plane, and the workpiece is gradually cut into various shapes.