Measuring the permeability of metallic objects

AI Thread Summary
To measure the permeability of irregularly shaped objects for finite element simulations of low-frequency magnetic coupling, one effective method is to create a coil and measure the inductance with the object inside. This approach allows for adjusting the permeability in simulations until the results align with the measurements. Typically, permeability is measured using toroidal cores for accurate values, but in practical scenarios, air gaps can dominate the magnetic flux, leading to simplified assumptions of infinite permeability. Additionally, in cases of intense magnetic fields, saturation effects may become more significant than permeability itself. Accurate permeability measurement is crucial for reliable simulation outcomes.
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Hello everyone. I'm working on a project where I have to do a finite element simulation of low frequency magnetic coupling. But my problem is that I don't know the permeability of all the objects involved. Can anyone suggest a good way to measure the permeability of these objects ? The objects are quite irregularly shaped, i.e. not spheres or boxes or cylinders.

I have one idea myself. I could make a coil of sufficient size and then put the object inside this coil, and measure the inductance. Then I could set up an identical finite element simulation and then adjust the permeability of the object until I get the same results as in the measurement.
 
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Permeability of materials is normally measured on purposely-made toroidal cores, to get sensible values.

In normal life, if these objects are undesired, they have unit of infinite permeability. Often accurate enough, because air gaps rather than metals determine the flux. Or take 1000, then 10000, and observe no difference.

If the field is intense enough, saturation can be more important than permeability. Uncommon with separated objects.
 
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