The Magnet test is used to distinguish ferrous from non-ferrous metals; or, rather obviously, magnetic metals from non magnetic metals.
I found also, that it is important to have a magnet that works for you! If you need help finding a magnet, I suggest you check these cheap sources of where to find free magnets! Another useful test for scrappers is THE SPARK TEST.
The Magnet will become your weapon, and with it you will sort ferrous and non-ferrous.
Follow these steps:
Ferrous Metals
Ferrous metals are alloys of iron, and they usually stick to a magnet... BUT a common misconception is that steel is the only metal that attracts a magnet; This mistake can be an expensive one. There are actually 3 (THREE) common elements that pull to a magnet, and those are iron, nickel, and cobalt. (there are some others, but they are mostly rare earth metals. For example, gadolinium)
These three metals are known as ferromagnetic (ferro- the latin root for iron) at room temperature. Ferromagnetic, for all intents and purposes, is just a fancy way of saying "strongly attracts a magnet." So ONLY iron, nickel, and cobalt will have a force exerted on them by a magnet, nothing else.
Iron, is a common, cheap metal; Nickel is an expensive metal, more so then copper; and cobalt is even more expensive, more so then nickel. If your magnet gets pulled to a metal alloy, it contains iron, nickel, or cobalt (usually just iron).
Many other compounds (non-metals) can be magnetic, but these are easily distinguished from a metal alloy as they are usually ceramic; for example, ferrite.
Be warned; things that are not attracted to a magnet can still contain iron, nickel, cobalt, or a combination. Take for example, 304 stainless steel. It contains both iron and nickel and yet, it doesn't attract a magnet! (Actually, there are many different types; find out why some types of stainless steel aren't magnetic!)
Metals that stick to a magnet that you should know of:
Non-Ferrous Metals
Non-ferrous metals are generally non-magnetic (except for nickel and cobalt). It is worth learning to identify these scrap metals:
As you guessed, these metals are very valuable and will be easily distinguished from ferrous metals with nothing but a magnet. Only after you have been learning for a while, will you be able to sort metals by simple sight and touch.
I found also, that it is important to have a magnet that works for you! If you need help finding a magnet, I suggest you check these cheap sources of where to find free magnets! Another useful test for scrappers is THE SPARK TEST.
The Magnet will become your weapon, and with it you will sort ferrous and non-ferrous.
Follow these steps:
- Step One: Find a metal sample
- Step Two: Find a magnet
- Step Three: Place the magnet against the metal sample.
- Step Four: Pull the magnet away from the metal sample.
- Step Five: Obey the magic rule...
If the magnet sticks to a metal alloy, it is a ferrous (or nickel or cobalt) alloy.
Ferrous Metals
Ferrous metals are alloys of iron, and they usually stick to a magnet... BUT a common misconception is that steel is the only metal that attracts a magnet; This mistake can be an expensive one. There are actually 3 (THREE) common elements that pull to a magnet, and those are iron, nickel, and cobalt. (there are some others, but they are mostly rare earth metals. For example, gadolinium)
These three metals are known as ferromagnetic (ferro- the latin root for iron) at room temperature. Ferromagnetic, for all intents and purposes, is just a fancy way of saying "strongly attracts a magnet." So ONLY iron, nickel, and cobalt will have a force exerted on them by a magnet, nothing else.
Iron, is a common, cheap metal; Nickel is an expensive metal, more so then copper; and cobalt is even more expensive, more so then nickel. If your magnet gets pulled to a metal alloy, it contains iron, nickel, or cobalt (usually just iron).
Many other compounds (non-metals) can be magnetic, but these are easily distinguished from a metal alloy as they are usually ceramic; for example, ferrite.
Be warned; things that are not attracted to a magnet can still contain iron, nickel, cobalt, or a combination. Take for example, 304 stainless steel. It contains both iron and nickel and yet, it doesn't attract a magnet! (Actually, there are many different types; find out why some types of stainless steel aren't magnetic!)
Metals that stick to a magnet that you should know of:
- Iron / Steel / Ferrous
- 4xx Series Stainless Steel
- Scrap Carbide (made of tungston cabide in cobalt)
- Nickel
- Cobalt
Non-Ferrous Metals
Non-ferrous metals are generally non-magnetic (except for nickel and cobalt). It is worth learning to identify these scrap metals:
- Aluminum
- Lead
- Copper
- Brass
- Zinc
- Magnesium
- Pot metal
- Chromium (used in Stainless Steel)
- Pewter
- Titanium
- Mercury
- Gold (found in Scrap Computers)
- Silver
- Platinum (found in Scrap Catalytic Convertors)
As you guessed, these metals are very valuable and will be easily distinguished from ferrous metals with nothing but a magnet. Only after you have been learning for a while, will you be able to sort metals by simple sight and touch.
Its really cool that you are so enthusiastic to share your insights with the world. I've found that the scrapping game is pretty competitive around here, but have found a yard I like. Even if they pay 2 cents less for ferrous, they are usually higher than others and are friendly. I also get that "scrappers are thieves" thing around here but am making a point to change that perception with those that I interact with. Like you, I want to keep it honest and legal.
ReplyDeleteI do have a question for you: I work in a bike shop and was recently given permission to take all of the shop's scrap metal... awesome! Lots of aluminum and other valuable metals. I was wondering though, I haven't found anything in this blog about identifying titanium. Might you have any tips about that?
Thanks,
- Ian
I'm glad to hear about your fighting the good fight, because scrappers work hard enough to deserve a better name.
ReplyDeleteI did actually write a very small note on how to identify titanium using the spark test. My note is at the bottom, and is the 3rd bullet point.
Basically, when you hit it with an angle grinder, you will get EXTREMELY white sparks. Remember, there are many aluminum alloys that claim to be "titanium!" but they are just aluminum alloys with a little titanium added for strength. Good luck!
Thank you The Irrationalist! I look forward to your future posts!
ReplyDeletehow do you identify zinc
ReplyDeleteWhat about metals or alloys that are somewhat magnetic. I ran into a boat steering wheel that I believed to be stainless but a rare earth magnet would not stick fast to but then watched it roll as I moved the piece away (magent is round and was setting on end) I have also discovered several other fitting that have the same reaction
ReplyDeleteThis is a beautiful question and I'm glad you asked it!
ReplyDeleteIt sounds like these magnetic properties are only showing themselves when either the maunder, our the metal is moving relative to another. If you know much about electronics, you changing magnetic flux causes an electric current. In return, that electric current causes a "counter" force which acts to oppose the change of the magnetic field. What you are observing is a very beautifu example of this phenomenon, aka "eddie currents".
True dropping the magnet thought a foot our two of copper pipe. The magnet will actually hover for a few extra seconds!!!