Resistors
![]() | Basic requirements for resistors (still one of the most numerous component in circuits) are: | |
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![]() | Materials of choice include | |
![]() | Ta, Ta based alloys, and in particular "Constantan" (55% Cu, 44% Ni, 1% Mn), a resistor material with an especially small temperature coefficient ar, but a large thermoelectric coefficient). | |
![]() | Strange mixtures of conductors and insulators including "Cermet" (short for Ceramics - Metals), e.g. Cr - SiO2. | |
![]() | Details and data in the (future) link. | |
Heating
![]() | Basic requirements for heating elements are: | |
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![]() | The choice of a materials depends significantly on the range of temperatures envisioned. We have: | |
![]() | FeNiCr, FeNiAl alloys. | |
![]() | Pt, W, Ta, Mo - stable elements with a high melting point. | |
![]() | MoSi2 Among more industrial applications also used as heaters in dish washers - this is very aggressive environment! | |
![]() | Graphite (up to 3000 K in non-oxidizing gas). | |
![]() | Some details and data can be found in the links. | |
![]() | Overview of resistivity and temperature range for some materials | |
![]() | Maximum temperatures for some materials | |
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© H. Föll (Advanced Materials B, part 1 - script)