Predict Magnetic Permeability?

AI Thread Summary
Predicting the magnetic permeability of an alloy, particularly combinations of iron, nickel, and copper, is challenging and often requires empirical testing for accurate results. A rough approximation may be possible, with tolerances of around ±50%, but precise calculations are complex due to factors like crystal structure and atomic interactions. The discussion highlights the potential reduction in permeability with the addition of metals like zinc, silver, and aluminum. The user expresses a preference for practical experimentation over theoretical calculations, suggesting that casting and measuring samples may be more efficient. The referenced PDF provides valuable insights but is acknowledged as complex and daunting.
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Is there any way to predict an approximation for the magnetic permeability of an alloy? I imagine that getting accurate results would be near impossible without creating the alloy and then testing it, so I'm looking more for just an order of magnitude (10x) or even a tolerance of maybe ± 50% or less. Specifically, I'm looking for the permeabilities of various combinations of iron, nickel, and copper. It would also be nice to be able to see how additions of other common metals, such as zinc, silver, and aluminum, would affect the permeability of an alloy; although, I think each of those would reduce permeability. My goal is to get maximum permeability with my only source of nickel being a 75/25 Cu/Ni alloy.
 
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Doubtless you've searched Bozorth? I'm away from my copy , but he's all over the 'net.

But I'm no expert. Page 10 of this pdf is plenty to humble me.

http://www3.alcatel-lucent.com/bstj/vol15-1936/articles/bstj15-1-63.pdf
 
jim hardy said:
Page 10 of this pdf is plenty to humble me.

http://www3.alcatel-lucent.com/bstj/vol15-1936/articles/bstj15-1-63.pdf

That really is great work, but I pretty much gave up after page 11. If I'd have to figure out the crystal structure of an alloy, take into account the excess of positive or negative spins of each atom in the unit crystal, figure out how easily these excesses can be paralleled based off of the distance between the atoms, and such, I'd much rather just cast and label samples of different alloys and measure their pulling force on a certain magnet or measure/calculate how much they multiply the inductance of a coil of wire. I didn't want to waste materials on making samples, but if it would be that complicated to calculate the permeability, I'd rather choose the sample method. I appreciate the pdf.
 
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