Naturally conductive fibers or metallic fibers are developed from electrically conductive metals such as ferrous alloys, nickel, stainless steel, titanium, aluminum, copper, and carbon. Metal fibers are very thin metal filaments, with diameters ranging from 1 to 80 microns (µm). Officially called a micrometer, a micron (µm) is one thousandth of a millimeter. To illustrate the fineness of a metallic fiber of 1 µm, a comparison can be made between these fibers and the diameter of a strand of human hair which ranges between 70 and 100 µm.
Metallic fibers are typically produced by either using a bundle-drawing process or by a shaving process. The bundle-drawing process consists of bundling several fine metal wires then drawing them continuously and simultaneously from source metals.