Creating Magnets

[Sambuchi]

I was wondering how some of the first magnets were made.

I'm not interested in electro magnets, using other magnets to make magnets, etc.

I am more interested in...

• Lodestones "natural" but still wonder how they get their properties...

• Browsing the internet, found a post about Creating Magnets by Tapping.
  The post didn't explain much and the person doing the tapping had little luck.

Interested to hear what you have to say.

Tony

[reloadron]

Best guess I found:

The process by which lodestone is created has long been an open question in geology. Only a small amount of the magnetite on Earth is found magnetized as lodestone. Ordinary magnetite is attracted to a magnetic field like iron and steel is, but does not tend to become magnetized itself. Recent research has found that only a variety of magnetite with a particular crystalline structure, a mixture of magnetite and maghemite, has sufficient coercivity to be magnetized and become a permanent magnet. One theory suggests that lodestones are magnetized by the strong magnetic fields surrounding lightning bolts. This is supported by the observation that they are mostly found at the surface of the Earth; not buried at great depth.

I could believe that magnetite in close proximity to a lightening strike and having the right composition could become magnetized.

We had the grandaughter up over Thanksgiving and of all things she started playing with a batch of magnets I have. She really had a fascination for the things and those magnets kept that 5 year old busy for hours. Therefore we decided to get her a magnet science kit for Christmas which includes a lodestone.

Ron

[MrAl]

Hi,


God wanted to give man something to play with

It's interesting that everyone pays so much attention to magnets. If they payed that
much attention to electrons they'd really be amazed. Electrons are what we interact
with in our nature. Everything we touch, hear, taste, smell, see, involves interaction
between electrons (or photons and electrons). Magnets illustrate the amazing
properties of these things very nicely as we can then get a feel for what effect
their spin properties has on our experiences, but we experience that same thing
when we touch something, yet the distances involved are so much smaller they
dont even seem like they are really there at all so billions of people live out their
entire lives and never realize that they had been interacting with every single
object in their lives because of the electromagnetic force (ie magnets).

"The universe is just a pile of electrons and photons, and nothing else matters"

If you could learn to manipulate electrons, you could do almost anything.

I have to admit that i've always liked magnets too, and electricity. I think of magnets
and the electromagnetic force a bit differently than when i was a kid, but magnets
are still great to have. I use one small strong one in one of my flashlights to keep the
positive contact connected to the battery. It works great.

I think the thing that always got me was that a magnet seems to have some sort of
force without actually doing anything to get that force. Once it has that force,
it always has that force. The problem is that it is deceiving, in that a force doesnt
necessarily mean anything gets done. We could have a strong force but if it doesnt
move anything it doesnt do anything except maybe hold something in place.
When we want to generate energy, we have to have it move something, and then
that requires more input energy.
Similarly, we could squash a strong spring with some screw clamps and it would push
quite a bit on the screw clamps, but it wouldnt do that much for us that way.

Ok, i got a little off the subject here, but when you talk about magnets, you talk about
electrons, and when you talk about electrons, you talk about everything in existence
today

PS
I saw a program on an invisibility scheme, where a scientist worked out a method to
make something invisible using a special kind of material. How does it really happen?
By a special manipulation of the electrons in the material. By manipulating the
electrons in this way they no longer react to light the same way, so they take on different
properties that we as humans experience.

[jwax]

I recall a similar discussion here years ago. I posited that a magnet that picked up a piece of iron does work. Potential energy was added to the iron. The magnet can do that an infinite number of times, right? So that magnet on your desk has an incredible amount of potential for doing work, right?
As I recall, the argument was that it will take the same amount of work to seperate the iron from the magnet, so the net gain is zero.

[haklesup]

We had the grandaughter up over Thanksgiving and of all things she started playing with a batch of magnets I have. She really had a fascination for the things and those magnets kept that 5 year old busy for hours. Therefore we decided to get her a magnet science kit for Christmas which includes a lodestone.

That's cool so long as none of the magnets can be swallowed. Swallowing 1 magnet is usually not a big deal but 2 or more can clamp portions of the intestine together causing perforations and serious medical threats. 5 year olds are still susceptable to swallowing toys. Many toys have been recalled in the past because magnets can be broken out of the toys that contain them.

In general bring a piece of iron up to the critical temperature in a magnetic field and it will become magnetic. How magnetic depends on the material properties and alloy of the iron. Lightning is a perfectly reasonable way to create high temperatures and a magnetic field inducing large current flow.

Some forms of iron with sufficient crystaline structure can be magnitized without high temperatures, hence the tapping but I need to research further to know the exact mechanism for that mode of magnitizing. Simialrly one can align the magnetic domains (necessary to observe bulk magnitism) of the iron grains by continued proximity to another magnet (hence the magnetic screwdriver tip which wasn't that way when it was new)

[Dean Huster]

We have a Briggs & Stratton engine plant here. They cast the non-magnetized magnetic poles into the aluminum flywheel and during assembly they "charge" the magnets using a high current and electromagnets.

[reloadron]

Well the little one loved her magnet set. She is an interesting kid. Rather than dolls (she has several) she seems to gravitate to things like magnets and other stuff along those lines. We got her a little kids camera last year and in to time at all her mother's computer was loaded with images. The dog was her main subject. Poor Brutus would run to hide when he saw the camera come out.

Alexis is very good about not eating things or putting anything in her mouth. However, my view is simple when it comes to children, they need constant adult supervision.

Magnets are just something that seem to possess a certain "magic" about them which makes them a fun toy.

Ron

[Sambuchi]

In general bring a piece of iron up to the critical temperature in a magnetic field and it will become magnetic. How magnetic depends on the material properties and alloy of the iron. Lightning is a perfectly reasonable way to create high temperatures and a magnetic field inducing large current flow.

This is what I was understanding with the other post. He was using the Earths field to make a magnet from iron!
I wonder if your position on Earth matters for a stronger magnet
Love it!

Some forms of iron with sufficient crystaline structure can be magnitized without high temperatures, hence the tapping but I need to research further to know the exact mechanism for that mode of magnitizing. Simialrly one can align the magnetic domains (necessary to observe bulk magnitism) of the iron grains by continued proximity to another magnet (hence the magnetic screwdriver tip which wasn't that way when it was new)

I look forward to see your findings. This subject is interesting... the "making something from nothing"

Everyone have a safe and great new year.

Tony

[haklesup]

I wonder if your position on Earth matters for a stronger magnet

The direction and strength of the field (in rocks) does very much matter on the position on earth when it was formed (cooled from molton rock usually but also relevant to sedimentary rocks). This is one of the cornerstones of geology that lets scientists work out the positions of continents at drift and wandering of the north pole. Even non magnetic rocks usually have enough iron grains to measure the field direction when they were formed. Pair this up with data relating to the age of such rocks and you have a goldmine.

[dyarker]

I recall a similar discussion here years ago. I posited that a magnet that picked up a piece of iron does work. Potential energy was added to the iron. The magnet can do that an infinite number of times, right? So that magnet on your desk has an incredible amount of potential for doing work, right?
As I recall, the argument was that it will take the same amount of work to seperate the iron from the magnet, so the net gain is zero.

Relative to the magnet the last sentence is correct. By the iron coming closer to the magnet the magnetic field has an easier path and you have net of zero when you pull the iron away. Any work lifting the iron would be done by whatever is holding the magnet.