| Anvil |
| Hi. Does any of you have a list of permeabilties of different metals. I would like to know permeability of copper, u-metal, stainless steel, aluminium and steel. What other things matter to magnetic shielding than permeability? |
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| weinstro |
| quote: | | I would like to know permeability of copper, u-metal, stainless steel, aluminium and steel. What other things matter to magnetic shielding than permeability? |
Relative Permeabilities
Iron 150
Permalloy 8,000
Nickel 110
Steel 50
Mu metal 20,000
Copper 1
Aluminum 1
Stainless 1 (depends on composition)
Personally, I would be looking at how the material is to work with, i.e., cutting, drilling, welding, bending, etc.
Regards,
Rob |
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| Anvil |
| Hi. What happens to stainless steel`s permeability when it is heattreated or welded? Thank you for your list. |
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| Steve Eddy |
| quote: | Originally posted by Anvil
What other things matter to magnetic shielding than permeability? |
Thickness and saturability come to mind. Generally the higher permeability materials saturate at much lower levels and once the material saturates, it's no longer effective as a shield.
se |
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| jneutron |
| quote: | Originally posted by Anvil
Hi. Does any of you have a list of permeabilties of different metals. I would like to know permeability of copper, u-metal, stainless steel, aluminium and steel. What other things matter to magnetic shielding than permeability? |
John...nice graph, thanks..
Anvil...skin depth of the material plays a role also.
depth (cm) = 5033 * sqr(p/uf)
p is resistivity in ohms per centimeter cubed
u is permeability for low flux densities
f is frequency
When SS is welded, it can allow precipitation of carbon, rendering it magnetic. Also, it can become slightly magnetic when machined.
Cheers, John |
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| sreten |
| quote: | Originally posted by Anvil
What other things matter to magnetic shielding than permeability? |
Fresh air, i.e. distance is much cheaper then anything else.
:) sreten. |
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