A question about permanent magnets !.

[Bulbz]

I'm a bit in the dark with this question. I'm still scratching my beard quite a lot because of this (or whatever is left of my beard, anyway :-O). How much energy does it actually require to manufacture a neodymium magnet.

I've looked all over the web, and if I have to scratch my beard any longer, I will end up having to scratch whatever is left of the hair on the rest of my head. As you can probably guess, I'm truly puzzled.

Thanks in advance.

[IronHead]

I am not certain , but if you consider the energy stored . The hundreds or thousands of years these things might operate would far out weigh any manufacturing energy consumption .

So build on Magnet motor builders/researchers
IronHead

[z_p_e]

I'm not an expert on the subject of magnetization, but there is info available on the net that gives the process.

In general however, if you have a coil around the raw magnet material, and energize the coil to such a level that it fully "saturates" the material, the remnant magnetism will be slightly less than what was used to magnetize the material.

In fact, it is common practice to slightly "demagnetize" the sample after full magnetization to improve stability and repeatability.

So, in the end, the strength of the magnetizing field, will have to be somewhat greater than what is remaining in the magnet after the process.

If you know the gauss rating of your magnet, you will have an idea of what was used to magnetize it.

Darren

[IronHead]

I think "Bulbz is asking about the entire process . From mining , extraction, purification ,forming ,hydrogen annealing and finally magnetizing of the processed magnet . A very complex and rather extensive calculation if you include the human labor as well. But then again it is not that much different than steel or lets say something  more rare, Titanium and the Titanium alloy process .

[z_p_e]

Hmm, he didn't specify, so I assumed he meant from the magnetization point of view.

A magnetic field is the output or end result, and I assumed he wanted to know how much "magnetism" went into making it, vs. how much we get back from the magnet, and for how long.

The magnetization process takes only a few seconds, yet the magnet could work for hundreds of years.

So to me, that is the pertinent comparison, and the only one that interests me anyway.

Darren