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Coercivity of Neodymium magnets, could it be demagnetized in an MRI?

by magnetics
Tags: coercivity, demagnetize, neodymium
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Nov4-12, 11:10 PM
P: 32
An N45 Grade Neodymium Rare Earth magnet has a remnance (Br) of 1320 mT and Coercive force (Hcj) of 923 kA/m.

I am a little confused with the units of Coercive Force, how does A/m relate to Gauss/Tesla?

Also, if an N45 magnet was placed inside a 2T MRI, would that be strong enough to demagnetize it or change its magnetic properties?

Thank you.
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Nov5-12, 07:16 AM
P: 11,925
Corresponds to ##\mu_r \approx 1140##

Putting strong magnets in an MRI looks like a bad idea, but I don't know how that would influence the magnet.
Nov5-12, 11:32 AM
P: 1,970
The relationship between B and H in air is B=μo H.
The 2T correspond to a value of H higher that the coercive field of the magnet so it looks like it can be demagnetized by this field, if the field is in the right direction.

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