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?
Don
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.
Don:
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:
formatting link
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?
Don
There was no such suggestion. Learn how to read.
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.
-Aut
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?
And, what is "watter" anyway? Learn to spell!
Pittsburgh Pete
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
Read the first question.
so? It's a metal.
Neither I nor the asker imply such property from a sheer element.
Onely you do, as you cannot read or think wrihtly.
I had. Organics are not even metals, and alloys call for metals.
Otherwise it'd be a compound.
It's what you drink and bear. You learn to spell.
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