If you wanted to drastically reduce the conductivity (increase the resistivity) of a metal, what sort of alloying elements could be used? I'm talking about very high resistivity...in the semiconductor range. I don't care what the base metal is, as long as it isn't wildly exotic or expensive. I just need very low conductivity, but with the formability of metal. Are there alloys like this that already exist?
I don't think so. Metals and semiconductors like silicon because they conduct. I don't think there are any metals or metal alloys which are as resistive as semiconductor silicon. There are ceramics and cermets which are highly resistive, but they aren't formable like metals. Metals are formable because the crystal planes can slip over each other. Ceramics and cermets lack that property.
What you are asking for is not going to come from a metal alloy. Formability (presumably at room temperature) and extremely high resistivity do not go together for metals or their alloys.
The previous suggestion of pure manganese is just silly because it is not an alloy and likely would be brittle. See:
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notes that pure manganese has a resistivity (at 25 C) of 185 microhm-cm. In Volume 2 of the ASM Handbook the conductivity for pure manganese is listed as being 0.9% of that for pure copper (IACS). So, the resistivity would be 111 times that for copper. It is far from a semiconductor.
Typical alloys also are discussed in the chapter on "electric resistance alloys" in Volume 2 of the ASM Handbook. Common ones are based on 75%Ni-20%Cr-3%Al plus 2%(Cu, Fe, or Mn). One commercial example is "Evanohm R" with a resistivity of 133 microhm-cm. See:
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You might do better by looking at polymer films. Go to
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and put "conductive polymers" in the search box at the upper right corner.
Pittsburgh Pete
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It notes that pure manganese has a resistivity (at 25 C) of 185
See:
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Thanks Pete:
A polymer just might work. I have tried graphite-filled plastics in the past, but I need contact with the entire surface of a sheet, which I have found to be difficult and inconsistent with just simple contact. It works much better with a conductive coating like copper or silver on the surface. Unfortunately, most of the plastics used in graphite-filled applications are not suitable for electroless plating.
In the link you provided, I did run across "polyaniline", which is a truly conductive plastic (no graphite). This is intriguing. I wonder if it can be electroless plated.
Does anyone know of a source where I might obtain samples of this polyaniline?
As he did say metal, and manganese is a metal, then it has the formability of metal. Pfft. But why does he want a metallic alloy rather than a semiconductor? He could disguise metal's shininess as a oxygel-compound with watter, or a glassy kalc=F2gen (sulfur). Minerals are the active ingredient in "metallic" paint.
The original question ended by asking... "Are there alloys like this that already exist?" Your reply was to mention a pure metal NOT an alloy.
He also said "I just need very low conductivity, but with the formability of metal." Now, the definition of formability is "the ease with which a metal can be shaped through plastic deformation". Pure manganese is probably brittle, and thus LACKS any useful formability.
The original question asked for "very high resistivity...in the semiconductor range". Your reply was to mention an element with a resistivity way below a semiconductor. You never bothered to even say WHAT the resistivity of manganese was!
Why did you bother to hit the return key when you had not answered the question in any USEFUL way?
this is a good question resistance in metal is the result of electron "collisions" I would assume that to increase a metals conductivity a metal with a smaller atomic radius with a larger valence shell but this is a vast generalization and more information is needed let know if i can provide more assistance
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