Post 429 –by Gautam Shah
A Wire is a thin section material. It is long drawn or extruded in a single strand. Wires due to their process of formation have strongly aligned molecules or chains, giving it high degree of tensile strength. Wires during the production processes and due to the smaller section is highly susceptible annealing and surface hardening, and so acquire unique properties of malleability, hardness, etc. Wires generally have round section but could have square, rectangular or flat, oblong and serrated forms. Wires are of solid section but could also be of hollowed section.
Wires are made of metals, metal alloys, dual metals, glass and synthetics (Nylon, polypropylene, polyesters). Wires and filaments have similar properties, and the names are often used synonymously. Similarly spun fibres of natural or synthetic origins have few properties that are similar. Wires are used alone, singly or in strands, as encased with plastics, paper, rubber, and other composite materials, entwined or braided as ropes.
Wires due to their thin section have strong anisotropic properties that are directionally dependent, compared isotropy, which implies identical properties in all directions. So wires are used for carrying the tensile loads such as for ties, ropes, hangers, etc. Wires of different metals and stiffness are used in stringed musical instruments for sound resonance. Wires are used as the cutting edge for building stones, precious stones, cheese, butter and flour dough. Wires of certain alloys can be re-stressed to form coils and springs. Wires due to surface hardening combined with flexibility cannot be shear cut and move under high impact and so have been used as strands and as woven structure for shields for armour. Stiff wires are used for hangers, compressible connectors, reinforcement for handles in bags and purses, and spectacle frames. Very stiff (hardened) wires are used as cycle spokes, combs for carding cotton, wool, etc. and as weft separators in looms.
Wires are very long linear products so form the continuous feed stock for production of nails, paper pins and clips, stapler pins, paper binding straps, needles, hairpins, other linear items produced with CNC machines, for soldering and continuous welding. Wires form the main body for electrical cables, encased with paper, asphalt, polymeric insulation, shielded or encased in other metal coverings. Wires are included in a selvage of clothes for very heavy curtains, sail fabrics and automobile tyres. Wires are used as bailing material for cotton, wool, and paper wastes bundle.
Wires are used for straightening the teeth, holding bones together. Guts (dried and stretched animal intestines) a form of natural wire was till now used for surgical stitches. Wires are used as clothes line, fencing or barricading media, and as lightening arrester.
Wires as long strand is used in many different compositions. Some are linear compositions, popularly known as multi stranded wires, cables and ropes. Entwined wires with twisted barbs are used for fencing. Clutch, gear changing and break wires for two wheeler bicycles and automobiles. Springs of ball pens to railway wagon buffers, sofas, cables for chain-pulley devices, cranes, guys for supporting tall towers and masts, coiled wires for bulbs’ filaments. Entwined wires are used for rubbing clean the insides of boiler pipes and tubes. Zari or metallic wires used for brocade weaving work and for decorative laces. These are very fine Gold. Silver or polyester wires entwined on polyester or copper cores.
Wires as a plain, long strand, multi-strands, entwined form are used for weaving planer compositions, such as wire clothes, screen printing bolting clothes, wire nett, sieving media, and paper pulp forming screens. Wire screens or woven lattices are used in agriculture to keeps off birds. Wire fabrics are used to catch signals.
Wires are used to create space or 3D forms, such as in kitchen drawer baskets, luggage trolleys, packing stones for retaining walls, filigree style of light weight jewellery and for rolling shutters. Construction plain bars and rebars are form of wires.
Metal wires are formed by drawing or pulling a linear piece or rod, through gradually receding sizes of holes. Synthetics and Glass wires are formed by extrusion or a spinerette. Drawing is a cold working process, but it may also be performed at elevated temperatures. Generally a drawing process heats up a wire to cause molecular changes. Gold and Silver are ductile but costly materials, so are co-drawn with a core of copper. Wires for jewellery are further dented, textured, chained or spring looped to create special effects, such as for bangles, bracelets, etc. Strips of drawn metals are passed through crescent shaped dies to form half or full hollow tubes.
Two or more wires are wrapped concentrically but separated by insulation, to form coaxial cable. Stranded wire is composed of several smaller gauge wires. It is more flexible than solid wire of the same total cross-sectional area. It is also a better conductor than solid wire because of the greater surface area. At high frequencies, current travels near the surface of the wire because of the skin effect, resulting in increased power loss in the wire.