Is Mu-Metal the Solution for High Permeability Applications?

[Hami Hashmi]

Does mu metal have a negative susceptibility and soft iron have a positive susceptibility?

 

[Hami Hashmi]

If the magnetic susceptibility is greater than zero, the substance is said to be "paramagnetic"; the magnetization of the substance is higher than that of empty space. If the magnetic susceptibility is less than zero, the substance is "diamagnetic"; it tends to exclude a magnetic field from its interior.

 

[berkeman]

If the magnetic susceptibility is greater than zero, the substance is said to be "paramagnetic"; the magnetization of the substance is higher than that of empty space. If the magnetic susceptibility is less than zero, the substance is "diamagnetic"; it tends to exclude a magnetic field from its interior.

So which is used for magnetic shielding, and why? Did you read the tutorials at the Magnetic Shield Corp. website that I linked to?

 

[berkeman]

Also, from your original question, it sounds like you are trying to figure out how to build something:

If you had a box made of mu-metal and and a magnetic material inside the box, then took an insulated wire and wrapped outside the mu-metal box and applied a current, then applied a magnetic field outside the box, which one would magnetize the mu-metal, even for a brief amount of time? Also, if the current outside mu-metal will magnetize it, would applying an insulator on top of the mu-metal help?

Can you say what you are wanting to build? Maybe if we knew that, we could answer your questions in a more helpful way.

 

[Hami Hashmi]

I'm trying to figure out how to block the infinitely strong magnetic and electric field from two electrons that are 0 m apart (since the electric field is dependent on the distance between the two charges and the magnetic field is dependent on the electric field). I know this is not practical but i just want to see if i can do it.

 

[Hami Hashmi]

And i did read most of those articles (the ones relating to magnetic shielding) but the only thing i found was that mu-metal has a low coercivity so it absorbs electric fields.

 

[berkeman]

the only thing i found was that mu-metal has a low coercivity so it absorbs electric fields.

No, that is not correct. mu-metal is not used for electric field shielding, and the value of Hc is not directly related to its magnetic shielding properties and uses.

I'm trying to figure out how to block the infinitely strong magnetic and electric field from two electrons that are 0 m apart (since the electric field is dependent on the distance between the two charges and the magnetic field is dependent on the electric field). I know this is not practical but i just want to see if i can do it.

Since this is for a thought experiment, it is especially important that you learn more about magnetic and electric fields at a fundamental level. What is your school background so far? What math and physics classes have you taken? Have you tried using Hyperphysics and the Khan Academy videos to learn more about these subjects? Without a good knowledge of the basic physics involved, it will be very hard for you to think accurately about how to manipulate fields.

 

[Hami Hashmi]

Opps sorry i meant to say magnetic fields.

I'm currently doing university physics but i have not reached the section on magnetic and electric fields yet. As for my math background, i have just started calculus.

 

[Vanadium 50]

I'm trying to figure out how to block the infinitely strong magnetic and electric field from two electrons that are 0 m apart

This isn't going to work.

First, if they are at zero distance apart, where do you put the mu metal? More realistically, atoms are larger than electrons. There's no place to put them. More realistically still, the magnetic properties of a material are properties of the bulk material, not individual atoms. Mu-metal is not an element, it's an alloy. You need between a million and a billion atoms for the bulk properties to fully manifest themselves.

 

[Hami Hashmi]

Here are some files.

 

[Hami Hashmi]

@Vanadium 50

I'm not actually going to put mu-metal, i am just trying to figure out how it works differently from soft iron so that i can make the lining similar.

 

[Vanadium 50]

If you need to use fantastic and non-existent properties of your materials (like their size), why are you restricting the other properties of your non-existent material to be realistic?

 

[Hami Hashmi]

Size?

And the material is theoretically possible except for the distance of the electrons and the up quarks from each other.

 

[Hami Hashmi]

I just need to figure out how to get the lining to absorb the magnetic field from the magnet.

 

[berkeman]

Thread closed for Moderation...

 

[berkeman]

Thread will remain closed.

@Hami Hashmi -- you need to learn more basics of E&M and fields and about magnetic materials before you spend too much time thinking up exotic (non-physical) thought experiments. Work through some of the online courses at the Khan Academy, or take some basic physics and EE classes at your local community college. With a better understanding of the physics behind E&M, you will be thinking of even better (and more physical) thought experiments and questions to ask at the PF.

Have fun leaning more E&M.