What are some common thermoelectric materials and their properties?

[zynko]

I wanted to do an experiment that had to deal with thermoeletric materials, and the out but of electricity. Does anyone know of a common thermoelectric material? Maybe somthing around the house? If not then just name off what you know. I want to see the output of electricity compared to the mass, volume, and temp of a thermoelectric amterial.

 

[Nenad]

what do oyu mean, like copper?

 

[zynko]

Well, a thermoelectric material turns heat into electricity. that's what i mean.

 

[Gonzolo]

You need two different conductors. In principle, any two different conductors can do. But some alloys have been developped so that they provide greater responses, or linear ones for specific temprerature ranges. The specific alloys that are used may be difficult to come by. If you only use one material for a thermoelectric effect, you can't really measure a good voltage because your probes will be at different temperatures.

A first experiment could be two try out whichever metal wires are available to you. Hold the wires parallel to each other, twist them together at one end (many twists for a good contact) so that you have a Y-shape. Heat the twisted end and meaure the voltage between the cold ends.

 

[zynko]

Thanks for your help guys, especially Gonzolo. I'll try to the thing with two wires and see what i get out of that.

 

[Gonzolo]

This provides a voltage, but not an accurate one :

Take a small piece of metal (a staple, a dime, etc) and pinch your voltmeter probes at each end. Using a soldering iron and without touching, heat one end of the sample, near a probe. You should get a voltage. A small soldering iron is probably the most practical heat source for such experiments.

 

[Locrian]

Omega has a great deal of information on thermocouples:

http://www.omega.com/

Though they do not have the best prices.