Electromagnets suffer from temp coefficients?

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Electromagnets experience changes in resistance due to temperature variations, requiring higher voltage to maintain power. The ferrous metal used in electromagnets has a Curie temperature, which affects its magnetic properties. The permeability (mu) of the metal varies with temperature, being highest at mid-range temperatures and decreasing at extremes. Once the Curie temperature is reached, the electromagnet's effectiveness is significantly diminished. Iron's Curie point is approximately 700°C, which is beyond typical operational limits for many applications.
Cliff_J
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Ok, so the wire used in an electromagnet will likely have its resistance affected by a temp change on a PTC and thus require a higher voltage to maintain power, simple enough. But will an electromagnet also suffer temp coefficients for induction and coercivity and have a currie temp too?
 
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The ferrous metal of the electromagnet will have a Curie temperature, and the mu of the metal will have a temperature coefficient. Usually the mu is highest at mid-temperature, and lower at the hot and cold extremes. But once you hit the Curie temperature, ker-plop.
 
Thanks. With proper spelling I now see that iron has a Curie point of around 700C which is well beyond what I need.
 
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