Curious as to how permanent magnet is produced / manufactured

How it is done today, and back then (say 1800s) Plus, anyone ever successfully created one at home? Thanks

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FrenchCrawler10 years ago
To make a permanent magnet out of ferrous metal, you need to heat it up until it's glowing, then strike on it while it's in a magnetic field until it's cooled (you can just point the metal north and strike the metal, but that creates a very weak magnet).

Here's the Instructable I did on it a while back

gyromild (author)  FrenchCrawler10 years ago
Hei..thanks frenhcrawler.. btw, have you tried the stroking method? will it produce stronger magnets? wonder if they used similar methods (or combinations of it) in commercial magnet production..
I didn't try the stroking method (mainly cause I moved onto new ideas) but it probably would make sense that it would make the magnets stronger. And as LasVegas said, they use huge electromagnets to make magnets in the commercial world.
LasVegas10 years ago
When I worked for Magnetic Peripherals (now Seagate) building Hard Disk Drives (SMDs w/ 4-6 12" platters with 300-500 MB capacity) they used a huge electromagnet with a large bank of capacitors and a mercury switch to charge the magnets. This device sounded like an explosion every time it was used.
gyromild (author) 10 years ago
From my limited knowledge, magnetism does occur naturally in certain rocks, ie lodestone... Come to think of it..It seem quite possible that there were actually magnet mines back then.. But, I'm also not sure if these rocks were directly used in the inventions/ discoveries/ industries of that era..
I'm not sure but I think back then they collected them from a rock known as magnetite. Well, I know there are natural magnetic rocks known as magnetite, but I'm not sure if thats what they used back in the 1800s. As for modern day neodynium magnets, I have no idea.