WEDM, also known as Wire Electrical Discharge Machining or low-speed wire cutting, is a CNC machine tool that uses continuously moving fine metal wires (referred to as electrode wires, usually copper) as electrodes to discharge electrical sparks to the workpiece in pulses, producing temperatures above 6000 degrees Celsius, and erode and cut the metal into the desired shape. The principle of WEDM is the phenomenon of continuous discharge removing metal due to the presence of a seam gap between the on-line electrode and the workpiece.