Metal: no attraction to magnet and block magnetic fields?

[tallatghazi]

Hi,
Can anyone help me in finding out a Diamagnetic or Paramagnetism or Ferromagnetism or any other metal which has following capabilities:
1- Should not be attractive towards magnet.
2- Should not allow magnetic fields to pass through inside.

Thanks!

THG

 

[berkeman]

Hi,
Can anyone help me in finding out a Diamagnetic or Paramagnetism or Ferromagnetism or any other metal which has following capabilities:
1- Should not be attractive towards magnet.
2- Should not allow magnetic fields to pass through inside.

Thanks!

THG

Welcome to the PF.

You say you don't want it attracted to a magnet -- can it be repelled? Or do you not want any forces on your shield at all?

If it can be repelled, you might be able to enclose with a ferrous shield inside of a diamagnetic shield...

 

[tallatghazi]

Thanks for you reply, yes the material CAN be repelled by magnet (as Diamagnetism) but issue is that material also should have capability of not letting any magnetic fields passing through it self.

Allow me to explain:
I know Pyrolytic Graphite or Bismuth metal repel Magnet but what will happen when 2 magnets being placed side by side (South pole of one magnet facing North pole of other magnet), sandwiching with a normal thickness plate of Pyrolytic Graphite or Bismuth? Does both magnets attract each other?

 

[tallatghazi]

Minor Repelling force or no Force at all both will work.

 

[berkeman]

Thanks for you reply, yes the material CAN be repelled by magnet (as Diamagnetism) but issue is that material also should have capability of not letting any magnetic fields passing through it self.

Allow me to explain:
I know Pyrolytic Graphite or Bismuth metal repel Magnet but what will happen when 2 magnets being placed side by side (South pole of one magnet facing North pole of other magnet), sandwiching with a normal thickness plate of Pyrolytic Graphite or Bismuth? Does both magnets attract each other?

Can you say more about the application? It looks like the poles of the 2 magnets will still attract each other...

http://images.tutorvista.com/content/magnetism-matter/diamagnetic-specimen.jpeg

 

[Baluncore]

If you block a magnetic field then it will push back on the magnet that generates that field.
Consider levitating a magnet above a superconductor, also consider a sheet of aluminium slowly falling between the poles of a magnet.
If it was an AC magnetic field you could use a sheet of aluminium or copper thicker than about twice the skin depth.

 

[tallatghazi]

Can you say more about the application? It looks like the poles of the 2 magnets will still attract each other...

http://images.tutorvista.com/content/magnetism-matter/diamagnetic-specimen.jpeg

How magnetic fields will behave as per attached image (if we will increase the height+width of diamagnetic shield)?
Will fields of both magnets interact with each other?

 

[tallatghazi]

If you block a magnetic field then it will push back on the magnet that generates that field.
Consider levitating a magnet above a superconductor, also consider a sheet of aluminium slowly falling between the poles of a magnet.
If it was an AC magnetic field you could use a sheet of aluminium or copper thicker than about twice the skin depth.

My concern is that I need to find a material which repels or show no force to magnetic fields + also magnetic fields of both magnets should NOT interact with each other.
Regarding super conductor, it also not work. Check this video

 

[berkeman]

Well, if you are going to deflect or guide a magnetic field, that will cause some forces. Can you say more about the application? There may be some other solution.

 

[Baluncore]

There are a couple of dynamic tricks you could consider.

1. A spinning conductive disk will drag the flux along with the disk and prevent magnetic communication between the sides while the disk spins. For two magnets you might consider a two sided disk with an insulator between.

2. Reactive armour, or a magnetic chameleon. By measuring the magnetic field over the surfaces you could generate current loops to zero that field. Maybe something like that will cancel your nearby magnet and render the screen invisible to the magnet. It might need two layers of loops with a mu-metal sheet as the core.