Identify Metals

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     If your like me and make scrap metal sculpture then it can sometimes be hard to identify what metal the scrap is made of. In this instructable I will show you how too identify some of the more common metals. NOTE: These are not all the metals there are, there are thousands and I couldn't possibly tell about all of them. Also if you bend tin it will make a light "snapping" sound.

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Step 1: Ferrous or Nonferrous?

     Ferrous means that the metal has iron content which in most cases makes it magnetic and nonferrous means it doesn't have iron in it. An example of a ferrous metal is mild steel, also known as low carbon steel. An example of a nonferrous metal is copper or aluminum. Its always a good idea to bring a magnet to the scrap yard.

Step 2: Aluminum

     Aluminum is a shiny grey metal and has a clear oxide that forms on contact with air. This may not be the best thing for identifying it, but aluminums melting point is 658° C (1217°F). Also aluminum is non sparking. Aluminums density is 2.70 g/cm3, this is a good way to identify it because you can find the density of a material by density = mass ÷ volume. As i said earlier, aluminum is nonferrous.

Step 3: Bronze

     Most bronze is an alloy of copper and tin, but architectural bronze actually has a small amount of lead in it. Bronze has a dark coppery color and gets a green oxide over a period of time. bronze's melting point is 850-1000°C (1562-1832°F) depending on how much of each metal is in it. Bronze is nonferrous. Because bronze is an alloy densities vary. Bronze vibrates like a bell when hit.

Step 4: Brass

     Brass is another copper alloy but it has zinc instead of tin. Brass has a yellow gold color. Brass' melting point is 900-940°C (1652-1724°F) depending on how much of each metal they used. Brass is nonferrous. Because brass is an alloy its density varies. If hit brass vibrates like a bell, this can be used to determine if something is brass instead of gold.

Step 5: Chromium

     Chromium is a very shiny silver color and forms a clear oxide over time. Chromiums melting point is 1615°C (3034°F). Things are rarely made of pure chromium but lots of things are coated with it to make it shiny and not rust. Chromiums density is 7.2 g/cm3. Chromium is nonferrous.

Step 6: Copper

    Copper is made into many alloys like brass and bronze. Copper is light red in color and gets a green oxide over time. Copper is nonferrous. Coppers melting point is 1083°C (1981°F). Coppers density is 8.94 g/cm3. Copper, like brass, also vibrates like a bell when hit.

Step 7: Gold

     Gold is a shiny yellow color and does not have an oxide. Golds melting point is 1064.18°C (1947.52°F). Gold is very soft and is very heavy. Gold has a high electrical conductivity (more electricity can pass through it) which means that the connectors on many cords have gold plating. Golds density is 19.30 g/cm^3. Gold is nonferrous. Gold is a "precious" metal which means that it is very expensive and is used in coins and jewelry.

Step 8: Iron

     Iron is ferrous (finally!) and magnetic. Iron is a dull grey when unpolished and its rust is a reddish color. Iron is also used in a lot of alloys like steel. Irons melting point is 1530°C (2786°F). Irons density is 7.87 g/cm3.

Step 9: Lead

     Lead is a dull grey when unpolished but shinier when polished. Lead has a relatively low melting point, 327°C (621°F). Lead is nonferrous. Leads is very heavy, its density  is 10.6 g/cm3.

Step 10: Magnesium

     Magnesium has a grey color and develops an oxide that dulls the color. Magnesiums melting point is 650°C (1202°F). Magnesium is extremely flammable in a powder or thin strips. Magnesium burns very brightly and is very hard to put out because it is so hot that if you throw water on it, it separates it into hydrogen and oxygen, two very flammable gasses. Magnesium can also burn without oxygen making it even harder to put out. Magnesium is very light with a density of 1.738 g/cm^3. Because magnesium is so light it is used in engin blocks in cars, and because it burns so brightly it is used in incendiary weaponry (to incinerate things) and fireworks.

Step 11: Mild Steel

     Mild steel is black to dark grey unpolished and silvery polished. Mild steel has the same red rust oxide as iron. Mild steel is also ferrous and magnetic. Another name for mild steel is low carbon steel. Mild steel makes yellow sparks when ground down. Mild steels density is about 7.86 g/cm3but it varies since it is an alloy of iron and carbon (low carbon steel). MIld steel melting point is 1350-1530°C (2462-2786°F).

Step 12: Nickel

     Nickel is shiny silver when polished and is darker unpolished. NIckel is one of the few metals that is not an iron alloy that is magnetic (5¢ US nickels are not magnetic because there made of a copper nickel alloy). Nickels melting point is 1452°C (2645°F). Nickels density is 8.902 g/cm3.

Step 13: Stainless Steel

     Stainless steel is a shiny silver color and does not forme and oxide. Chromium (step5) is mixed into the steel, when it hardens the chromium leaves a coating of its oxide on top of the steel, this is too thin to see so the steels color shows through. Stainless steels melting point is from 1400-1450 °C (2552-2642 °F). Stainless steels density varies because it is an alloy. Depending on the alloy some stainless steels are magnetic, but all are ferrous.

Step 14: Tin

     Tin is silvery grey in color (like most metals) when polished and darker when unpolished. Tin has a comparatively low melting point of 231°C (449°F). Tins density is 7.365 g/cm3. Tin is nonferrous

Step 15: Titanium

     Titanium is a silvery grey metal metal when unpolished and darker when unpolished. Titanium gives off bright white sparks when it is ground. Titanium is nonferrous. Titaniums melting point is 1795°C (3263°F). Titaniums density is 4.506 g/cm3.

Step 16: Silver

     Silver is a shiny grey even before being polished but develops a black film over time and has to be polished. Silvers melting point is 961.78°C (1763.2°F). Silver has the highest electrical conductivity (more electricity can pass through it) than any other metal. Silvers density is 10.49 g/cm^3. Silver is nonferrous. Silver is a "precious" metal meaning that it is expensive and is used in coins and jewlery.

Step 17: Zinc

     Zinc is naturally dull grey and is very hard to polish. Zinc has has an oxide that flakes off carrying some of the zinc so other things are coated in it so the zinc "rusts" instead of the base metal, this is called galvanization. Because of its low cost zinc is the main metal in us pennies. Zincs melting point is 419°C (786°F). Zinc is nonferrous. Zincs density is 7.14 g/cm3.

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    118 Discussions

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    GinnaJo

    Question 7 months ago

    Hi.
    This pale gold pendant has no markings and is soft to scratch. I do t know what it is, any idea?
    Thanks in advance
    Jo

    15462582383482138745140847201344.jpg15462583650699070318468011552932.jpg
    1 answer
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    RenmarM

    4 months ago

    I just want to ask if my item have a value? Pls. Contact me

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    GAPeach0519

    Question 5 months ago on Introduction

    Hope this works this time! Trying to figure out how to polish this beautiful adjustable arm lamp I bought! I used magnet and all three sections are ferrous! Thought it was brass before that but it is kind of heavy...any suggestions??! I took more pics but they didn't post. If you can help I xan send more pics!! Thanks again!

    15510311886239160720616057980210.jpg
    1 answer
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    GAPeach0519GAPeach0519

    Answer 5 months ago

    Here's another image...cant figure out why I can't post others?!

    1551031569160677254691319040301.jpg
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    Japhetd

    6 months ago

    Hallo I’m working on a project and I have to determine which type of metal those material are made of, I did some research and ended up with a conclusion that they where Iron because they are magnetic, grey, it’s easy to make marks on them. So I wanted you guys to give it a look and help to to confirm that those parts are made of Iron or another metal. Thank you

    image.jpgimage.jpg
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    Muzdug

    Question 10 months ago on Introduction

    My grandfather gave me this chunk of metal that he said was imbedded in the rock platform at the beach and chipped it out, and was wondering if anyone new what it could be from or was s part of, it’s really heavy.

    FEE18305-BD76-4A36-A0C4-44D4F3C1FE3A.jpeg4746E39F-8A1C-4019-8F14-BFBD175658FD.jpeg2ADD8731-D4FD-4BA6-AAE7-2A38B3346D16.jpeg03A0059F-1276-4F1A-A22D-EBDFFA65BF23.png
    1 answer
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    JenniferM522Muzdug

    Answer 7 months ago

    Recently lost my place to a fire and that looks like what I found left glass, metal and rock that all melted and fused to gather. Sorry probly wasn't much help.

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    ScottP219Josh V Carpenter

    Answer 11 months ago

    Maybe; there is not much info in the picture. I was hoping that this instructables page had, well, instructions, but I can help.

    I doubt that the part is aluminum because aluminum is soft and rather inexpensive which would make it unlikely to be cast into shape. I also see that there is a square notch known as a keyway in the center hole; this would be for transmitting torque which would usually be done by a part made out of alloy steel, but could be stainless; possibly but not likely for aluminum.

    Most stainless steel is somewhat magnetic, so try sticking a magnet on the part and get a feel for how strong the magnetism is. Then find a known piece of either stainless like a stainless steel pan (which would also have weak magnetism) or a known piece of steel such as a cast iron pan (stronger magnetism).

    If the part is non-magnetic, it may be an aluminum alloy or austenitic stainless steel, which would look a lot like aluminum, but much harder and more dense.

    A hardness test can be as simple as using an exacto knife to try and scrape a little off of the part; aluminum is very easy to scratch while steel is hard.

    I think that the part in the picture is likely an alloy steel which would have small amounts of nickel and chrome (around 1-2% depending on type) and is cheaper and easier to machine or cut than stainless steel.

    Of course, I could also argue that it may be stainless steel because that would help justify the fact that the part was cast.

    One more possibility that I can think of is that the part is a titanium alloy; titanium looks a lot like steel (not stainless), while having a lower density than steel but higher density than aluminum. Titanium is annoyingly hard to cut and potentially flammable. I suppose that you can test this by carefully using a grinding tool on the spokes or something to try and create sparks.

    In the end, there is simply not enough information in the picture to be sure.

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    RachelB222

    Question 11 months ago

    ive got an old urn type thing i was told it could be very old has faces like i

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    Jack A LopezKariA20

    Answer 1 year ago

    Any person can tell you the worth of an object to that particular person. All you have to do ask. E.g., "Would you buy this sculpture for $10? For $100? For $1000?"

    Or you ask the question a different way. You can ask for a bid, i.e. ask, "How much money will you give me for this?" Then you can choose to decline offers that are too low, or choose to accept offers you think are high enough or higher.

    However, beauty, or worth, is always in the eye of the beholder. Thus it is hard to guess what the average buyer, or all the buyers (i.e. the market place) thinks is an worthy price for your thing.

    You might be naively thinking that worth, or price, is objective, but it is not. It totally depends on the desires of the buyer(s) for your thing.

    Besides you did not even ask about what kind of worth, e.g. worth as art, or worth as scrap metal.

    A scrapper sees worth only in terms of the work required to rip a thing apart, and the masses of various metals it contains, and how much money he or she can get for those metal pieces metal from a scrap buyer.

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    NoahK40

    1 year ago

    This is cool. I spent a whole school day in middle school reading this. We didn't really have any work

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    gearskin

    8 years ago on Introduction

    Stainless steel and aluminum both form an oxide layer called a passivation layer that is non-porous to oxygen, thereby protecting the interior of the metal from further oxidization.

    2 replies
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    eager to learn2gearskin

    Reply 2 years ago

    Without blemishing the metal with HCL acid or scraping it with a metal grinder, how can one differentiate between stainless steel -vs- aluminum? I've read you can't detect by sight or weight. Does either ping like crystal? Which professionals are considered experts in differntaiting metals? Thank you!

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    Philwhippleeager to learn2

    Reply 1 year ago

    Isn't stainless steel a ferrous metal and aluminum a nonferrous metal?

    Ferrous or Nonferrous
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    philln

    2 years ago

    I'm trying to figure out an easy way to distinguish cast aluminum from forged aluminum. (in those cases where the obvious signs of a cast piece have been removed) How about whether the mfrs markings are raised lettering (as in cast) or stamped (as in forged)? Or maybe hit it with a big hammer and see if it cracks in two? Thanks

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    twopussez

    2 years ago

    SuperElephant - It's called a euphonium and TRUMPET not Trumpit ya tuba.

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    super elephant

    8 years ago on Step 4

    this is not a tuba or a baratone, and for other posters, it is not a trombone, trumpet, or a baratone horn. THIS IS CALLED AN EUPHONEUM
    (You-phone-E-yuMM). As proof, i play euphoneum, trumpit, trombone, baratone, and tuba! I also have facts here.

    This is a tuba, it is extremely large, heavy, and has 4 valves faceing outwords, a short bell, and all adjustment slides are on the inside. the picture posted on this instructable can not be a tuba. (the first picture is a tuba)

    this cant be a baratone. It has a long bell pipe, and it doesn't have so many adjustment pipes,has 3 valves, sometimes 4, alvays pointing out, not up like a trumpits, and onley one tuneing slide. the picture posted on the instructable is not a baratone.(the baratone is the second picture)

    this cant be a trombone because a trombone is long thin, has a long slide, and sometimes has one valve, BIG difference.(trombone is picture # 3)

    a trumpit is about 1 1/2 feet long(sizes verry slightly), thin, and has three valves pointing up. (trumpit is picture # 4)

    a baratone horn is like a trumpit, onley slightly larger than a big trumpit, witn a big bell. (baratone horn is picture # 5)

    Finally the euphoneum, the euphoneum is like a baratone, onley with a short wide bell, always 3 valves pointing up, and many tubes inside and out. the picture is an euphoneum (the euphoneum is picture # 6)

    tuba.bmpbaratone.jpgtrombone.bmptrumpet.jpgbaratone horn.jpgeuphoneium.jpg