what's the best way to generically describe a material that will attract a magnet?

Greg Bernhardt

My sister has a question:

thanks!

Greg Bernhardt

My sister has given be perhaps a better way to ask:

Greg Bernhardt

Could one use the term "permeability" or "electromagnetic material"?

Studiot

There are two types of magnetic materials.

Those that react to an external magnetic field only when the field is present and those that retain a magnetic effect after removal of the field.

Further the reaction may be classed as paramagnetic which reacts to reinforce the applied field or diamagnetic which reacts to oppose it.

Ferromagnetic materials can be regarded as very strong paramagnets that retain a magnetic effect after removal of an applied magnetic field. They can generate a magnetic field in their own right without being energised and are called permanent magnets.

hope this helps, but remember this is very broad brush.

Greg Bernhardt

Thanks Studiot! It does help, but I she is looking for an all encompassing term.

So far we have:

"High Permeability Material"
"Electromagnetic Material"
"Magnetic Material"

Which one of those would be use in industry?

I like Serena

To keep it as generic as possible, I guess you might say: highly permeable material.

Note that slightly permeable materials (paramagnetic materials like aluminium) don't really do the job.

But to be honest, I don't know which term would be used in industry.

Edit: electromagnetic materials and magnetic materials would be different beasts.
In particular a magnetic material would already be magnetic itself, which would be a subset of highly permeable materials.

Greg Bernhardt

I guess my next thought for that would be that the term permeable is used is so many different sciences that it becomes ambiguous without context right?

I like Serena

Good point, so I'd make it highly magnetically permeable material. :)

And here's another one: magnetically susceptible material.

Studiot

I think most folks would say magnetic material if they meant material that 'would attract a magnet'

It is often recommended to check used cars with a magnet to test for hidden body filler.
Also many types of stainless steel do not attract magnets so they (magnets) are often used in workshops to distinguish steel types.

In both cases the users say the material is magnetic or non magnetic.

I like Serena

Magnetizable material?

Since magnetic material implies it's already magnetized.

Greg Bernhardt

true, since an iron plate would attract a magnet, but it is not polarized correct?

I like Serena

Exactly!

Studiot

Sorry to disagree but you did want an industrial answer.

You can buy magnetizable tools (screwdrivers etc) and which can be magnetised along wiht magnetizing units - that is they can become permanent magnets.
These are well known in industry.

Attaching one of these magnetising units to the side of say a filing cabinet or fridge (or a fridge magnet) will not magnetize the cabinet, but you will cetainly feel the force of attraction.

turbo

I think ferromagnetic material might cover it well enough. It is not necessary for the material to contain iron.

I like Serena

Interesting!
What is a fridge door made of?

As it is, I can't find a distinction between materials with high permeability, ferromagnetic/ferrimagnetic materials, or materials that become magnetized when exposed to a magnetic field.
Is there a distinction?

Btw, apparently a fridge door is usually made of iron.
And a fridge magnet is usually not a simple bar magnet, but it has alternating north and south poles.
Apparently this gives the magnet twice the magnetism on one side, and hardly any magnetism on the other side.

uby

a "magnet" can come in two forms.

first is a ferromagnetic material that has been at least partially polarized by exposure to an external magnetic field that is locked in by thermal treatment about its curie temperature. as a result of this locked-in polarization, the material generates an external magnetic field.

second is an electro-magnet, in which a solenoid will generate an aligned magnetic field due to electronic current.

a "magnet" will "stick" only to a ferromagnetic material. a directionally-dependent force is generated as a result of the interactions of the two magnetic fields.

a paramagnetic material (or a diamagnetic material) does not generate an external magnetic field, though it will affect their propagation due to the formation of induced dipoles.