Titanium, how to tell?

Sam Salvati

Sam Salvati

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Aug 6, 2007
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I got these two peices of mystery metal, I am not sure just what they are. They feel much lighter than steel of equal size, one has a purple colored patina, the other a blue. On side is smooth the other is precision ground looking. My question is, how could I tell wether they are steel or titanium? Will a spark test work? I have definate titanium samples to test with, or is the spark difference THAT much different?
 
Titanium sparks are bright white. That should be pretty easy to spot.
 
We metallurgists just look at metals to tell what kind they are !!!..Sam ,What kind of answer do you expect after I hacked away at slush and ice for two days !!
 
Weigh them and determine their volume:
Get a measuring beaker from the kitchen, add enough water so that the part can be fully submerged. `take the part out again and let it dry. Add a bit of water to the beaker so that you're at a nice round reading. Write it down. Then submerge the part and write down the new reading and subtract them. Then you know how many cc's of material you have. Next, weigh the part. Divide the weight by the number of cc's. Now you have the density of the material. Titanium comes in at around 4.45 grams per cc, aluminum at 2.7-2.8 and steel around 7.8.

If the part is too big for the beaker:
Take a container of suitable size. Fill it with water and add the part. Mark the water level. Take the part out again (let as much water as possible drip back into the container). Put the container with the water on a scale, if possible zero the scale. Add water until the mark is reached and determine the weight of the water you added. Water has a density of 1 gram per cc, so grams=cc's.

Cheers rody
 
#1 use a magnet. Ti is non magnetic.
#2 Spark Test it. once you see TI spark you will never forget it.
#3 Ti is much lighter than steel. though not a difinitive test it can help.

Unless you are trying to tell the difference in alloy then you need a spectra graph.
 
OK, thanks for the tips guys! ROBERT I FEEL YOUR ICY PAIN!!!!!!!!!!!!! What torture this nasty ice is.

I tested my two peices, no sparks at all on the grinder, then I tested my peice of titanium and WOAH Chuck you are right once you see TI spark you will NEVER forget it! Turns out that it must be aluminum, but the weird thing is it is just so DAMN FLEXIBLE. It is one peice 1/8th thick by about 4 inches wide, and another 1/8th thick at about 6 inches wide both about 15 inches long, and I am HARD PRESSED to bend either one, let alone enough to take a set. Can aluminum be heat treated?>!?!?
 
I originally thought they were heat treated steel, being one has a purple patina much like the oxidation color spectrum/temper colors and oen being blue, they sure do not feel like regular aluminum.
 
See if it will anodize.

Clean a portion of the mystery metal bright and shiny –
I mean sandpaper…

Put into a solution of TSP - (tri sodium phosphate - hardware store paint aisle)
Cola drinks also work in a pinch (it's the phosphoric acid that does the trick)

attach the + end of a DC power supply to the mystery metal – even a paperclip works here to attach the wire – just keep the wire and paperclip out of the solution.
Attach the - end of a DC power supply to a bit of stainless steel and drop the stainless steel in the solution
A 9 volt battery can be used - or a plug pack from some electronic equipment

6 to 24 volts are all common and quite usable
Colours will range from straw to gold to purple, blue and pink

6al4v gives a lovely purple colour at about 18volts


If this works, you can be sure it is a reactive metal
Definitely not aluminum and most likely titanium

Steve
 
I recently got a piece of what was described as aluminum from Craig's list. It is 3.5"x 6.625x 8.25. $15, she had got it from a storage auction. On the way home I got to wondering the same thing. Was it Aluminum or the jackpot piece of Ti. I weight it at 18.5 then by multiplying the dimensions for volume then by the weight per cu inch. Came out right at 18.5 so I knew it was aluminum with just a tape and a calculator.
 
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