finewire

Fine wire is a class of electrical conductors characterized by very small diameters, typically from several micrometers up to about 0.5 millimeters. It encompasses magnet wire with enamel insulation used for windings, as well as insulated or bare single- or multi-strand wires used in compact electronics, sensing devices, and jewelry. Wires in this class are chosen for combinations of high conductivity, tensile strength, flexibility, and corrosion resistance.

Materials commonly used for fine wire include copper and copper alloys for good electrical conduction; nickel or stainless steel for strength and spring properties; nichrome for resistance elements; and precious metals such as gold, silver, and platinum for corrosion resistance and specialty applications. Diameters are specified in micrometers or in American Wire Gauge (AWG) values for practical use, with finer wires requiring careful handling.

Manufacturing is typically by drawing, a process that reduces a starting rod to the desired diameter, often followed by annealing to relieve work hardening. Many fine wires are coated or insulated to prevent short circuits and chemical degradation; magnet wire uses enamel, while others may use polymer coatings or multi-layer insulation. Some fine wires are stranded to improve flexibility.

Applications of fine wire include transformers and motors, microelectronics interconnects, implantable medical devices and neural probes, sensors and actuators, jewelry making, and craft applications. Selection depends on conductivity, tensile strength, corrosion resistance, and compatibility with coatings or insulation. Standards cover diameter tolerances, insulation class, and testing procedures.