# Magnetic shielding

http://www.kjmagnetics.com/blog.asp?p=shielding-materials I understand from the diagrams that the magnetic field is redirected through the shield (and not canceled out.. etc) Suppose I cover one magnetic pole of a bar magnet with a magnetic shield. Would there be less attractiveness in the immediate area beyond the shield in contrast to a corresponding area around the other pole? Can I achieve something similar to the concept the image portrays of shielding part of a magnetic pole?The field lines are to be simply taken as a perceptible difference in attractiveness between each sides of the magnetic poles

Suppose I cover one magnetic pole of a bar magnet with a magnetic shield. Would there be less attractiveness in the immediate area beyond the shield in contrast to a corresponding area around the other pole? Can I achieve something similar to the concept the image portrays of shielding part of a magnetic pole?

Aka

Within reason yes, BUT the laws of Physics and Murphy will (simultaneously) follow you doggedly no matter how hard you try to shake them off.

Halbach array: A Halbach array is an arrangement of magnets that provides an assymetric field by arranging poiles so that the fuelds cancel on onbe face.It can be made in circular and planar arrangements and has special applications in motor magnetic bearings (aka levitation) and high energy density motors.

Launch Point HA motor makers

[NASA report - Halbach Magnetic Rotor Development - 2008]( http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20080013147.pdf)

If this is an attempt to make something approaching

• a Monopole [tm] (A Halbach array comes closer than most things)

• a static magnetic field levitator *

• a free energy device

• a perpetuum mobile

• an over-unity device

• anything which equates static magnetic field alone with energy flow

• or similar "fellow travellers"

then you may have as much fun as the many people on the web who attempt to create such devices, and about the same amount of success. (About zero is effectively equal to zero).

FWIW - long ago, knowing that it had been proven that you cannot statically levitate an object using permanent magnets, I tried to do so regardless, using constructional methods that might be expected to work were it not impossible :-) - ie dished monopole "bowl" with other poles underneath and a monopole-outside ball. As entirely expected, I did not succeed, but I learned a lot about the lengths magnetic devices amd Murphy will go to to protect their theoretical integrity :-)

Related and possibly relevant:

• You can achieve levitation with a stationary magnetic field if your target is a suitably shaped rotating magnet. cf the Levitron levitating 'top'.

You CAN achieve static levitation if you include a diamagnetic material in the "magnetic circuit".

UCLA - diamagnetic levitation

... and many more

Wikipedia - magnetic levitation

Wikipedia - diamagnetism

• And superconductors are strongly diamagnetic, but unfortunately all the ones discovered to date only work at very low temperatures. – Spehro Pefhany Jun 30 '14 at 12:15
• @SpehroPefhany there exist many High Temperature Superconductors at higher than 120 K which is substantially above Liquid Nitrogen temperatures ( 77 K) which is generally recognized as the boundary at which it is feasible. It certainly isn't room temp, but it's for the most part very practical and obtainable. "Very low temperatures" is, in this field very misleading. – placeholder Jun 30 '14 at 16:48
• @placeholder Yes they exist. But there are two different kinds of Superconductors. The Meissner effect in Type 2 superconductors isn't as complete as in the Type 1 superconductors(all high temperature SC are type 2). A nice side effect is that you can "freeze" them in the flux(kind of) to create a floating magnet, which is really nice :-D. – WalyKu Dec 4 '14 at 15:06