mimic said:
hi all, Please can you help list materials that can be used to Block, Reduce, Stabilize, Increase or react with the fields from perminant magnets
The magnetic field from a permanent magnet is just that - a magnetic field, it is no different from the magnetic field produced from an electromagnet. The last three words in your sentence are hence redundant.
il start with
Graphite: A Magnetic Stabilizer
Coper: A Magnetic Inductor
This is a misleading description - to say, without elaboration, that graphite is a "magnetic stabilizer". There is no material property known as magnetic stability. Graphite is a moderate diamagnet. When used in the right geometry, it provides a shallow potential well for a magnetically levitated object (again, only in a specific geometry), which results is better stability against mechanical perturbations.
Second, it is meaningless to say that copper is a "magnetic inductor". Inductance is a geometrical property, not a material property. Copper is essentially non-magnetic
**. The reason copper is used in transformer windings is because of its large electrical conductivity. You'd have to build a significantly larger transformer if you wanted to use some other (eg: aluminum) material to deliver the same current through the windings.
In any case, to add a little to your list :
Mu-metal : A very high permeability ferromagnetic alloy made primarily from nickel and iron. It is often used in magnetic shielding.
##
Bismuth : This the the strongest elemental diamagnet at room temperature. It's diamagnetic susceptibility is a little bigger than those of gold and graphite and a lot bigger than those of copper and water, yet about 5 orders of magnitude smaller than that of a superconductor (in the Meissner phase).
** It is the weakest known elemental diamagnet, with a susceptibility smaller than -10^
-6.
## Note : In certain (eg : aerospace) applications where stronger shielding is required, superconductors are used for magnetic shielding. A superconductor is a perfect diamagnet with susceptibility of -1.