Wires are used in a wide variety of applications and come in many different forms and materials. Wires are used to power our houses, send phone calls and even used as fences. The three most common types are Solid, Stranded and Braided…
Solid Wire/ Single Core/Single Strand
In its most simple of forms, one piece of metal wire is often referred to as a Solid Wire. When wrapped in a non-conductive material for insulation (normally a plastic) we would refer to it as a Solid cable. Speaking in general terms, a Solid Wire is cheaper than a Stranded or Braided Wire, and will offer better corrosion resistance due to its lack of surface area. Although a Solid Wire will have a smaller diameter in comparison to a Stranded Wire this does not reduce its current carrying ability. Solid Wire are generally more rugged and stiff than Stranded or Braided Wire and although this increases their lifespan, it does make them unsuitable for applications where a lot of movement is needed, as an example in a sound system. Solid Wires do not have the appropriate malleability to be bent into awkward shapes.
A Stranded Wire comprises of a number of small wires all wrapped together. Stranded Wires are generally more expensive than Solid Wire, but are more flexible and able to withstand a great deal of vibration/awkward angles without breaking. Stranded Wires are more likely to fail as a result in corrosion in part because of their larger surface area and also in part due to the small amount of air present between the strands. These air channels will also amplify the “skin effect” created by the magnetic field along the cables’ surface. At higher frequencies a current will travel near the surface of the wire which results in an increased power loss.
Very similar to Stranded Wire, a Braided Wire is composed of a number of small strands of wire, braided together. This has the advantage of increased flexibility and better conductivity than a Solid Wire. In terms of the “skin effect” the way a Braided Wire is constructed, strands that start outside of the bundle will go inward. As the current ‘flows’ down the wire it will not follow that wire inside but rather transfer onto the adjacent one. As such good conductivity between the wires is crucial as otherwise AC resistance will be high.
In electrical applications, Copper has always been the most widely used material due to its low cost and high conductivity. Gold is of course a better connector and is used in some applications where long life and corrosion resistance is crucial, for example Gold is used in car airbag electronics. In the last ten years there has been a real growth in the use of ‘super alloys’ such as Inconel and Hastelloy for any mechanical applications due to their increased strength and corrosion resistance. The range of different wire materials to suit specific applications is growing rapidly.
What B&B offer
We have been working with wire manufacturers for over 27 years as a business providing outsourced tooling such as Rollers, Dies, Extrusion Shafts and more. We understand that all tools need to be harder than the material they are drawing and have a particular niche in the Hard Turning and Grinding of Powder Metallurgy Steel up to 69 HRc. We also have our own on-site metallurgist who can advise you as to the best materials to use on a range of different wire materials. We are fully ISO certified, work to your drawing and deliver across the UK.