Would heating and cooling a ferromagnetic material allow it to more easily take on a magnetic field

Question

I'm trying to magnetize various objects, such that they take on a strong magnetic field.

Theoretically, magnetism is caused by aligning electrons such that they stay more or less in the same place.

If i heat the electrons,  they're more energetic,  and thus likely won't be in the same place. But could i theoretically use the same system that an Air Conditioning unit uses ( compressed air can more readily exchange heat than uncompressed air ),  by aligning the electrons when they're more energetic, and cooling them down while still aligning them,  could that create a stronger magnet than just aligning them while cold?

eisi0523 · Answer

By aligning magnetic domains (ie. electron spins) you can create a very strong magnet in, for example, a ferrite. You can heat up iron for example to a specific temperature at which spins become less localized (ie. more mobile) and subject it to a very strong magnetic field that is created externally by say an electromagnet. The spins will align with said field and if you cool the iron down while maintaining the external applied field the spins will "lock in place" and remain aligned.

After some time though usually magnetization can fade due to various factors and the magnet can typically be "re-initialized" by repeating the previous process.

R.W. Bird · Answer

One needs to be aware that if you get a magnetic material too hot, thermal agitation will prevent the atomic dipoles from maintaining alignment. Also, when an external field is removed, the dipoles tend to relax into alignment with the crystal axes. The “remnant” field (after saturation) depends more on the nature of the material than on its history.

Answered by R.W. Bird on July 29, 2021

Would heating and cooling a ferromagnetic material allow it to more easily take on a magnetic field

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