The electrode wire should have good electrical conductivity and electrical corrosion resistance, high tensile strength, and uniform material. At present, the electrode wire materials used in wire EDM are aluminum wire, tungsten wire, tungsten-molybdenum alloy wire, brass wire, copper tungsten wire, etc. Molybdenum wire is widely used as wire electrode in fast wire cutting, and brass wire with a diameter of 0.1mm or more is widely used as wire electrode in slow wire cutting.

Tungsten wire has high tensile strength and the diameter is in the range of 0.03-0.1mm. It is generally used for the finishing of various narrow slits, but it is expensive. Brass wire is suitable for slow-speed processing. The surface roughness and flatness of the processed surface are good, and the adhesion of etched debris is small, but the tensile strength is poor and the loss is large. The diameter is in the range of 0.1-0.3mm. It is generally used for slow one-way travel. Silk processing. Molybdenum wire has high tensile strength and is suitable for fast wire processing. Therefore, most of China's fast wire machine tools use molybdenum wire as electrode wire, with a diameter in the range of 0.08-0.2mm. 

The selection of electrode wire diameter should be based on the width of the slit, the thickness of the workpiece and the size of the corner. If processing small molds with sharp corners and narrow slits, finer electrode wires should be used. If processing large-thickness workpieces or high-current cutting, you should choose a thicker electrode wire.

The winding of the wire electrode is the process of winding the wire electrode from the wire coil to the fast-moving wire cutting wire storage cylinder, and then threading it on the wire rack, which is called wire feeding and threading.