[sdiy] need linear and square resistance temperature coefficient

[Ian Fritz]

At 04:50 AM 8/12/2004, you wrote:

>I need the linear and the square resistance temperature
>cvoeffcient for Cu and Al.

Martin --

There is a theoretical expression that gives good fits to relative 
restivity changes for all elemental metals.  Doesn't work so well for the 
absolute values. It is given in terms of a Debye temperature Th.  Here it is:

r(T)/r(Th) = 4.225*(T/Th)^5*Integral(0 to Th/T)dz(z^5/((e^z-1)(1-e^-z)))

For Al:  Th=395K
For Cu: Th=320K

You could probably use Mathematica, etc. to get the derivatives you need. I 
have no idea how accurate this expression would be for the quadratic 
coefficient.

   Ian