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I would like to know if anybody has the seebeck coeficents for aluminum and/or
iron. Preferably in Volts/deg C
RE I need the Seebeck coeficent for aluminum and
R. Wallace Stewart (Ref.1) gives the following expression for the thermoelectric powers of several metals
dE/dT = a + 2bT
where,
E = electromotive force
T = temperature
a,b = constants
From this expression it can be inferred that the thermoelectric power (dE/dT) of each of the metals varies linearly with temperature.
Based on experimental results by Dewar and Fleming, the constants a and 2b which give the thermoelectric powers of aluminum and iron respectively in units of microvolts per degree centigrade are given as
Al a = -0.593; 2b = 0.00398
Fe a = 15.087; 2b = -0.01330
Therefore the thermoelectric powers of these metals at temperatures of 0'C and 100'C respectively may be taken as
Al -0.593E-6 V/'C and -0.195E-6 V/'C
Fe 15.087E-6 V/'C and 13.757E-6 V/'C
The experimental results upon which these figures are based were obtained a long time ago. However, I think it is unlikely that the physical properties of these elememts will have undergone any significant changes since that time!
Best regards,
Keith P Walsh
Ref.1 'The Higher Text-Book of Magnetism & Electricity', University Tutorial Press Ltd., London, 1906.
PS, I have assumed that the terms "thermoelectric power" and "Seebeck coefficient" are recognised as being equivalent in this context.
Im not sure about this,
Im not sure about this, shouldn't the TEP be varied referenced to absolute temperature rather than 0 °C ie
ΔS= a +2b (T+273)
If T is in °C.
The value could still be written as V/K or V/°C.
Im not trying to be picky, it is a useful little formula I just want to know how to use it properly. I hesitate to add that using K gives closer values to my measurements this afternoon but that means very little at this stage!!