which material is appropriate for "magnetic field" shielding?

Answer 1

I assume that you are referring to low frequency (or static) magnetic fields. Note that this answer may not apply to high frequency fields. The answer is more complex if the fields are changing. If you are interested in quickly changing fields, you should post a new question specifically about that.

There is no way to completely "shield" anything from a magnetic field because magnetic field lines must always find some path back to their source. (in other words, complete shielding is not possible due to the lack of "magnetic monopoles")

However, field lines can be gathered up within objects with a high "magnetic permeability." For example, an object made of iron will have a higher magnetic permeability than air, thus magnetic lines will tend to flow through iron objects more easily than they will through air.

Thus, if you can provide a highly permeable path for flux lines to return to their source, then that path will be followed more readily than paths through the air. (see the first source below for an example) Note that some lines may still pass through the shield, especially with large fields. However, less will penetrate the area "behind" the shield than would without it.

So you need to look for permeable materials. See the second source below for some examples. Note that *NOT* all metals are good shields.

You may want to check out the third source below, on "Mu-metal," which is a special alloy with a very high magnetic permeability. To quote it, "The high permeability makes mu-metal very effective at screening static or low-frequency magnetic fields, which cannot be attenuated by other methods."

Answer 2

any metal enclosure can be effectively used for electromagnetic shielding as the magnetic flux across a metal surface is zero. Magnetic lines of force can't enter a metal shielded enclosure.

Answer 3

i assume which you're bearing on low frequency (or static) magnetic fields. word that this answer won't word to extreme frequency fields. the respond is greater complicated if the fields are changing. in case you have an activity in quickly changing fields, you will desire to positioned up a clean question rather approximately that. there is not any thank you to fullyyt "shield" something from a magnetic container via fact magnetic container traces would desire to constantly discover some course lower back to their source. (in different words, finished protecting isn't achievable via shortcoming of "magnetic monopoles") although, container traces may well be accumulated up interior gadgets with a extreme "magnetic permeability." as an occasion, an merchandise made up of iron would have a greater robust magnetic permeability than air, subsequently magnetic traces would tend to flow by way of iron gadgets greater rather than they'll by way of air. subsequently, in case you delivers a rather permeable course for flux traces to return to their source, then that course would be observed greater without issues than paths for the time of the air. (see the 1st source under for an occasion) word that some traces would desire to bypass for the time of the shield, extraordinarily with super fields. although, much less will penetrate the section "at the back of" the shield than would without it. so which you will desire to seem for permeable components. See the 2d source under for some examples. word that *not* all metals are solid shields. it is incredibly helpful to check out the 0.33 source under, on "Mu-steel," that's a undeniable alloy with an extremely extreme magnetic permeability. to quote it, "The extreme permeability makes mu-steel very powerful at screening static or low-frequency magnetic fields, that could't be attenuated by potential of different approaches."

Answer 4

Aluminium.
Thickness would obviously vary on strength of magnetic field to be neutralised!