Understanding Magnetic Shielding - Is This Correct?

[Treborman]

I'm struggling to get my head around this concept.

As far as I know, magnetic permeability is a measure of the ease at which a magnetic field passes through a body. So if I used a highly magnetic permeable material (steel, aluminium) for a container to shield against external magnetic fields, the magnetic field would prefer, for want of a better word, to pass through the container's walls than through the container itself, and thus the magnetic field inside the container will not be changed from external sources.

Is this correct?

 

[berkeman]

Yes, that is correct. Maybe this website will also be of some help -- we use Magnetic Shield Corporation's products in some of our applications:

http://www.magnetic-shield.com/dynamics/index.html

 

[Treborman]

Thanks for your help! Much appreciated!