Stronger Than Steel and Conductivity
Date: Winter 2013-14
I have been fascinated by the growing list of materials that are said to be stronger than steel and enjoy reading about how such materials are changing the way many products are made. The articles tend to focus primarily on the strength of such materials, but they often go on to discuss other properties. One of the properties often pointed out is the electrical conductivity, often with the materials having excellent conductive properties. I am curious to know whether any material that is as strong, or stronger than steel, happens to have very poor electrical conductivity.
Thanks for the question. Spider's silk and Kevlar are materials that are stronger than steel and have poor electrical conduction. For more information, I would recommend doing a patent search or a literature search of scientific and engineering journals.
I hope this helps.
In fact, most materials that are pound-for-pound stronger than steel,
are not particularly good electrical conductors. Many, such as some
high strength composites, are good insulators.
Materials such as carbon fiber and carbon nanotubes can have
excellent electrical conductivity by themselves, but when bonded
together by (insulating) resins into useful parts, their conductivity is
mostly lost. Note that some sources claim that carbon nanotubes have
superconducting properties, but this has not been verified, and to date,
carbon nanotubes are still just a laboratory curiosity!
There are numerous high strength metals and alloys (for example,
titanium and its alloys), but none has significantly better electrical
conductivity than steel; in fact most are worse than steel. None
(including steel) even come close to the electrical conductivity of
Perhaps you have some examples of high strength materials that you
feel have excellent electrical conductivity?
"Strength" can mean many different things. When you're talking about
fibers, strength usually means tensile strength (pulling). The tensile
strength of aramid (Kevlar) is higher than steel, and aramid is a poor
electrical conductor. Another kind of strength is compressive strength
(pushing). Many minerals and ceramics have higher compressive strength
than steel, and they are typically nonconductive as well.
Hope this helps,
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Update: November 2011