What type of a magnet is really strong, not too big, durable,. .

In summary, you need a rare-earth magnet that is really strong, not too big, and easy to find. You can use it for something like lifting heavy objects, or for powering an electromagnet.
  • #1
apples
171
0
What type of a magnet is really strong, not too big, durable, and has a long life? Where do I get it?
 
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  • #2
How big? Do you mean small like cell phone size, or small like a penny?
 
  • #3
You're looking for a rare-earth magnet:

http://www.unitednuclear.com/magnets.htm
 
  • #4
Neodymium magents are awesome. They're so powerful they're like no magnet I've ever experienced.
 
  • #5
DaveC426913 said:
Neodymium magents are awesome. They're so powerful they're like no magnet I've ever experienced.

My old school had a 7T superconducting niobium magnet in liquid helium! Although they never did let me play with it.
 
  • #6
They're not that durable. One of my friends dropped one of MINE on the ground and it exploded into five pieces that all sucked themselves right back together from the magentism.
 
  • #7
lol.
I need one which is no bigger than around 4 inches in every dimension. And I need one which is easily available, not rare.
it doesn't have to be really durable you know, but durable yes it should be.
 
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  • #8
apples said:
And I need one which is easily available, not rare.
"Rare" Earth magnets are not rare.

You need to be specific with your questions. The magnets I work with are 10-16T magnets that weigh from 100-200 lbs. But they're very delicate. As far as I'm concerned, a strong and light magnet would be something giving me more than 15T at less than 100lbs. I'm guessing that's not what you want. On the other hand, for an NdFeB magnet, a 4" cube is GIANT!

That's why numbers are important! Descriptors like 'strong' and 'small' are too unspecific to be useful. What do you want to use the magnet for?
 
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  • #9
apples said:
What type of a magnet is really strong, not too big, durable, and has a long life? Where do I get it?

"Rare-earth" magnets refer to the "rare-earth" elements used in them, which are not "rare" at all:

http://en.wikipedia.org/wiki/Rare_earth_element

Permament magnets "last" forever, unless you roast them in an oven. The neodymium magnets listed on the United Nuclear page are basically the strongest magnets you can get; they are potentially dangerous. They are not durable though, quite brittle. You can buy them for a few bucks, or pull one out of a broken hard drive (watch out for sharp metal edges!).
 
  • #10
I need a light weight magnet, which has to be strong because it will be lifting quite a lot of weight, More than 30 KG probably(i don't know maybe 60kg!) that's why I"ll probably use 4 of them for more power.

But what I want is not this magnet to be the stronger one...
I want to use it in this way:
There will be an electromagnet... around 12 inches away, and when I turn it on it is supposed to pull this magnet, and there would be a rubber ring in between so they won't smash together... alignment etc. will not be considered atm. This permanent, which I need, would pull maybe 5 -I don't know how much 50(?)KG. I haven't estimated that yet. And I'm sorry that I am not much familiar with Telsa, so I can't give you an estimate in how much T i need. I know I'll need to study it before I continue, so I'll familiarize myself with all this after my exams finish.
So atm, I can just talk in childish language and say I need to pick up this many weight.
Anyway getting back to the point. Where was I? Yeah so the electromagnet would be the one pulling the weight and that has to be the one which is really strong... And I'll attach a potentiometer, so the I can regulate the strength of the electromagnet. How strong does the electromagnet have to be, what voltage should I supply? I don't know yet. I"ll have to figure that out as well. So this permanent magnet which I need is not supposed to be the stronger one. It just needs to be able to be able to pick up all that weight and go towards the electromagnet.
And why I need to regulate the electromagnet's strength? That's so I could change the speed with which the permanent magnet moves towards the electromagnet.
So you see, there's a chance that the rare neodymium magnet will crack under all that weight. And I don't want the permanent magnet to be too strong creating magnetic fields that might interfere in other things.

Thanks a lot.

EDIT: thnx for telling me about rare Earth magnets :). Silly me.
 
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  • #11
apples said:
it will be lifting quite a lot of weight, More than 30 KG probably(i don't know maybe 60kg!)
...
And I don't want the permanent magnet to be too strong creating magnetic fields that might interfere in other things.
These two things are about as opposing as you can get... Factor in a few hundred kg of soft iron shielding to your device.


BTW, you do realize that the electromagnets are going to have the same magnetic fieldmproblems as your perm magnets?
 
  • #12
Yeah, I do, and I know I have to do something about it. Still an electromagnet can be turned off. So that's not as big a problem.
But what about the magnet. What if stick a neodymium magnet in an iron casing. In this way, the magnet would be protected, but would it still be as strong? Because if a neodymium magnet is the strongest, then I think that would be needed.
Plus I think an iron casing would be essential in anymagnet.
 

Related to What type of a magnet is really strong, not too big, durable,. .

What makes a magnet strong?

The strength of a magnet depends on the material it is made of and its shape. Some materials, such as neodymium and samarium cobalt, are naturally stronger than others. Additionally, the shape of the magnet can affect its strength, with bar magnets being stronger than disc magnets of the same size.

What is the most durable type of magnet?

The most durable type of magnet is one that is made of a material that is resistant to corrosion and demagnetization. This includes neodymium and samarium cobalt magnets, as well as ceramic magnets.

What size of magnet is considered not too big?

The size of a magnet can vary depending on its intended use. However, for a general use magnet, a diameter of 1 inch or less is considered not too big. Keep in mind that smaller magnets may be less powerful than larger ones.

How do I know if a magnet is strong?

The strength of a magnet can be measured by its magnetic field, which is typically measured in units of Gauss or Tesla. The higher the measurement, the stronger the magnet. Additionally, you can test a magnet's strength by seeing how well it attracts or repels other objects.

What type of magnet is best for my needs?

The best type of magnet for your needs will depend on the specific application. Consider factors such as strength, size, durability, and cost when choosing a magnet. Consulting with a magnet expert or doing some research can help you determine the best type of magnet for your needs.

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