Reasons for miniaturisation
Miniaturised electrical conductors featuring a single-wire diameter of 0.05 mm or lower are used in signal cables and data transmission cables for the applications stated below:
- Aircraft (signal transmission to cockpit, communication, entertainment)
- Special electronic devices (mobile phones/laptops)
- Miniaturised coaxial cables
- Radar and sensor technologies (defense)
- Medical technology (heart catheters)
- Automotive (conductors for seat heating made from LEONI Histral® R15 and H18)
- Mobile phones and computers
- Functional clothing
For all these applications, the same challenges requiring solutions arise. To begin with, rising raw material prices have been triggering a strong trend towards cutting down the material input as far as possible throughout the entire manufacturing process. In addition, with space being a restriction, the allowable amount and volume of conductors to be incorporated in any of the above devices is limited. At the same time, the processes, which are controlled by means of electric signals, are growing more and more diverse so that an increasing number of functions has to be taken care of by each conductor. In particular when it comes to building automobiles, aircraft or aerospace vehicles, exceptional weight efficiency is requested nowadays in order to minimize fuel consumption. The flexibility of a strand constitutes another property that can only be accomplished by increasing the number of single wires used. Just take the following example: A strand composed of 19 wires with a diameter of 0.20 mm each will end up having the same cross-section (0.6 mm²) as another strand made up of 850 wires with a diameter of 0.03 mm each, with the flexibility of the latter being significantly higher.
Regardless of their reduced weight and diameter, miniaturised electrical conductors are required to meet or even beat the demands placed on their predecessors in many respects, above all as far as their tensile strength and flex life are concerned.
Particular manufacturing challenges
Miniaturising single wires and making them into strands translate into particular human and technological qualities required. All machines have to be specially geared towards extra fine materials. All operators involved need both an extraordinarily fine feel for the machine as well as a great deal of patience. On top of that, they undergo special training in order to live up to the task. All raw and input materials must be of an exceptionally high quality since the slightest impurity or irregularity may entail devastating consequences in the manufacturing process. Furthermore, the hygienic standards to be fulfilled by products applied in the field of medical technology are extremely high.
All materials used are expected to boast top-notch quality with regard to their tensile strength, flex life, conductivity and heat resistance, in particular when it comes to thermal stress upon further processing, for instance during the extrusion process. It goes without saying that we strictly use environmentally sound, RoHS-compliant materials.
Leoni offers a whole series of copper-based alloys lending themselves extremely well to miniaturisation, while perfectly meeting the aforementioned requirements, too: they all form the LEONI Histral® - Family