DHarris

Can Mystery Steel be ID’d by Density

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I have two 3 to 4 foot long pieces of 1.5” round stock of an unknown type of steel. I picked them up sometime last year at Nimmo’s, a salvage yard here in Purcell (now closed due to family illness). I spark tested them after I got them home and could see they contained carbon. I cut an inch off one of the bars to see if I could harden it. I was using a steel chop saw and it took a very long time to cut. I have never cut anything that thick before, but have quite a lot of experience with cutting angle, channel iron, and flat bar used to manufacture utility trailers and truck beds. Those cut like butter compared to this.

It didn’t harden much at all when I quenched the piece in oil, but hardened very well in water. 

Chris, one of the guys who posts here and is also a Saltfork Craftsman member is interested in making a hammer, so I took one of the two rods and a very large tie rod end to give him his choice of one or the other. With Korney’s help, we cut of a slice of the rod, heated it and quenched it in water. Chris then put the slice in a vice and hit it with a hammer to see if it would break. It did. I’ve attached the pics. The grain structure looks very small. 

The slice itself feels unusually heavy, which brings me to the point of this post. Is it possible to get even remotely close to an ID based upon density?  I work in a clinical lab so access to a certified scale and a graduated cylinder is not a problem. The density calculation itself is easy if you have that. 

The steel also feels ‘funny’, for lack of a better word, when sanding it by hand. It doesn’t sand easily but when sanded, the surface just looks great and has a wonderful feel to it. Lame description that doesn’t give any useful information, but it is the best I can do. I have always carried bits of wood, stone, or metal in my pockets to fiddle with when thinking or waiting. This little sliver of steel is very satisfying to carry.

Any ideas on how I could identify what sort of steel it is? Are there labs that could ID it for me? Cost isn’t really a concern for me. 

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I wonder if these could be pieces of drilling rod, also called sucker rod. Were there any more pieces, and were some of them threaded at the ends? Some also have markings in the steel.

I just noticed that you are from Oklahoma. Lots of oil wells out there.

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The best way to identify it is to match the spark pattern to a known piece of steel. This assumes you dont want to have a lab id it.

Without a known piece to test spark against, a spark test is a guess.

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Some junkyards have handheld spectrometers for testing mystery metals. You said you have access to a lab perhaps they have one. Maybe even a jewelry store but I'm just guessing about that.

Pnut (Mike)

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6 hours ago, anvil said:

The best way to identify it is to match the spark pattern to a known piece of steel.

I disagree about spark testing, because that is not best it is only a educated guess.   A chemical analysis like Gas Chromatography is the best way, he did say he has a lab

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I agree Steve. A gas chromatograph mass spectrometry test would be the best way to find out exactly what it is and what percentage of each compound or element it contains. No guesswork involved.

Pnut (Mike)

 

 

 

 

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2 hours ago, Steve Sells said:

A chemical analysis like Gas Chromatography is the best way

I agree with that.  I also saw his mentioning working  in a lab. I assumed it was not a lab that could identify steels. Thus my mentioning a lab to I'd it.

I have no clue as to the cost to have a lab identify a piece of steel. A sample board is relatively inexpensive and works best if you have a bit of experience.

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Gas chromatography or xray spectrometery will give you a good idea but neither is perfect. Calculating it's mass and density might tell you how far from low alloy steel it is but won't tell you what's in it. The higher the carbon content the lower the mass. 

The break looks darned granular to me, I wouldn't call it good but I'm looking at a pic on a computer so it's FWIW.

Steel that thick tends to bog hot saws down and cut slowly so that's no indication. The sparks coming off the blade is a better indicator but not a good one. Spark testing was reasonably accurate in the day of simple steels when there were only trace elements in them. Now steels are designer stews, things like: vanadium, manganese, chrome, molybdenum, cobalt, tungsten, copper, lead, aluminum, etc, etc, don't spark like steel, they aren't. 

If what the stuff is really matters it's lab time. You'll want to decide how accurate a result you want first. Running an xray spectrometer over a sample might run you $10 in a scrap yard where gas spectrometry is probably significantly more expensive and if you want a full blown chemical analysis you're looking at crazy money.

Frosty The Lucky.

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X-ray florescence or optical emission spectrometry would give the most accurate analysis but like frosty said who knows how much money that might cost.

Pnut (Mike)

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Clinical lab, as in a hospital. The only mass spec we have is a Bruker MALDI-TOF instrument used to identify microorganisms.

After looking at this chart I found today online, I think I should be able to get reasonably close.  There is some overlap, but I should be able to use other observable characteristics to rule a few out.  It is not stainless for example, so I can exclude that section entirely. 

I have considered trying to find an engineering student at OU in need of a little cash to run a few tests for me in their labs.

Density of steel chart at amesweb

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I don't think you can successfully identify alloy based on weight. The difference of .2% carbon to .8% carbon is humongous, but the weight change will nil. If you have a ton of nickel that could make it a bit heavier, and also the high alloy tool steels can get heavy with lots of tungsten etc. 

By far your best bet is to find a metallurgical test lab (college or commercial) and have them run an OES. Then you will have a truly analytic evaluation of the composition. 

I'd guess it would be less than $500 for one sample. If more I'd check around for another lab, should be able to find one for under $250 if you ask around. Usually they will need a slice about 1" square or so. 

I used to do this testing myself, so I'm fairly familiar with it. (Former metallurgist here with reverse engineering experience.)

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Mr. C' Steak,

Has added the post immediately above this effort.

Wherein, he states:  "By far your best bet is to find a metallurgical test lab (college or commercial) and have them run an OES."

The SLAG is not clear as to what  OES stands for. ( he anything but all-knowing.).

So He (I) consulted www.abbreiviations.com,  and got fifty possible abbreviations for OES.

It turned up possible candidates,  such as;

1)  occupation employment statistics,

2)  office of emergency services,

3)  order of the eastern star,

4)  old English sheepdog … ,

5)  original equipment supplier,

And 45 other possible definitions.

None of them seem to make sense in the context of his post.

I suspect that the S  of OES  may stand for spectrometer. But I will not bet on it.

Anyway reading this purple patch, discloses a very useful website, if nothing else. 

Will I ever discover the true meaning of OES?  We at SLAG Industries, are still researching this question.

Stay tuned you never know what we may find out.

Regards, to 

Mr. C' Steak, and other smiths here,

SLAG.

YIKES!  I just read the definition, (namely optical emission spectrometry), several posts above Mr. Chuck steak's.

Apologies are offered. 

And yours truly must, presently, wipe the egg off his face,  (OUCH!).

 

 

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3 hours ago, SLAG said:

And yours truly must, presently, wipe the egg off his face,  (OUCH!).

Your cat should be more than happy to clean egg off your face. If not you need a dog, ANY dog. There are no OUCHES involved in your dog cleaning food off your face, sloppy wet yes. Pain? Nope. ;)

Frosty The Lucky. 

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Dear Frosty,

My fortunate, frigid, friend,

I am happy to report that our house wonder felid,  (a.k.a.  cat),  'Litzie' did an admirable job of removing the egg from my visage,  (face).

I hope that this situation only arise occasionally in the future, or not at all.

Regards,

SLAG.

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I don't know why I can't remember Litzie's name, I'm usually much better with the pet names than the people.

2 hours ago, SLAG said:

I hope that this situation only arise occasionally in the future, or not at all.

Litzie will be disappointed you know. Maybe make it up to her by bringing her an occasional Egga muffin.

Frosty The Lucky.

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Mr. Frosty*,

Thank you for your suggestion.

Do not feel bad about not remembering Litzie's name.  She, too, does not recognize her name.

Being of the feline  persuasion, she is primarily a carnivore.  (but she does eat grass on occasion).

Cheers,

SLAG.

*  "the lucky".

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Mr. SLAG,

A good point about the abbreviation, even if covered previously. There's lots of acronyms and it's easy to blow past them.

Probably the OP (original poster) will be able to get an Arc-spark OES , which with modern equipment let's you get the carbon and sulfur content also. In the past, you needed to do a LECO (brand name) combustion for the carbon and sulfur and get the rest of the elements from the arc-spark. Then there is the lesser used GDS (Glow Discharge Spectroscopy). And if all you have are small samples of drillings, you could have an ICP-OES (Inductively Coupled Plasma) performed. And the super old school analytic way would be a true "wet chem" using titrations, but no one does that any more.

Either and any way, having a lab check for alloy chemistry and compare to the nearest grade shouldn't be a difficult exercise. 

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C-S,

Thank you for all the information.

I am going to delve into the subject further. (using Wikki and a search of the American chemical society (A.C.S.), web site.*)  as a matter of interest and curiosity.

Are you a metallurgist?  (your exhaustive knowledge is showing).

Yes,  I 'fondly' remember all the titrations that we did,  in stone age times!

Again,   thanks for your post, it is appreciated,

Regards,

SLAG.

* I'm still a member after all these years.

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2 hours ago, SLAG said:

 

Are you a metallurgist?  (your exhaustive knowledge is showing).

 

I am, my B.S. was in materials engineering, worked at a failure analysis lab for about 8 years. Was a WI professional engineer in Metallurgy.

It's lapsed now because I am currently a six sigma black belt at an injection molder. I moved to northern WI, and you take what you can get when it comes to engineering jobs. I did very much enjoy my metallurgy career, but like the lower population density of Price county a lot more.

OP-sorry for the thread drift. It was a very good question, I've been thinking a lot about the most cost effective ways to ID scrap using non analytical methods myself as my scrap pile grows.

 

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The best threads drift on and off topic, so no need to apologize. 

I have found density will not work. There is too much overlap. Besides, I found accurately measuring volume is much more difficult than measuring weight.

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Just to throw in another aspect which is really quite useless from a lay persons stand point and just to add another facet which is not needed. there is the expansion of such metals or alloys when heated as a test case or study.   :)

it's been years and years since i had read up on the exact ratio or how much expansion takes place at elevated temperatures and how they vary with alloys..  LOL..     Enjoy.. 

 

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That's why truly accurate density figures will always include "at STP" or the like.

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Was funny.  again pulling up from the old cobb webs, the difference was in 0.00001 or some such item. 

By the way.. Isn't that an oil treatment?  :)

 

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