Any method for determining material? (round bar) 1

[jgrady]

Hi,

I have a feeling I am out of luck but I have about 30 lengths of unidentified round bar stock. I was wondering if anyone could point be in the right direction for a process or even test to narrow down or determine what material we have.

Regards,
Justin

 

[metengr]

I would search for a Materials Test lab near you that has a portable alloy analyzer. They can send a Tech out to type the material at your facility.

 

[jgrady]

metengr,

Ok so from what I understand, this will give me chemical composition. What about grade? Strength of the material is also important, would I need to send a sample out for testing to determine this?

 

[metengr]

Yes. Full chemical analysis and hardness testing. Only a small wafer section is needed. Tensile testing could be done in lieu of hardness but this would require more sample material.

 

[jgrady]

What about temper, is there a way to determine from hardness or do you need a separate test?

 

[metengr]

Hardness.

 

[racookpe1978]

And, at a certain point, you are paying a great deal of money for certifying 30 pieces of scrap iron worth only 2.00 dollars per foot. Or $400,000.00 in penalties and lawsuits if you are wrong.

 

[metengr]

Not necessarily. This is done routinely in ASME code for identified material or lost traceability. Nothing out of the ordinary.

 

[WKTaylor]

I agree with Racookpe.

NOTE. For aerospace applications, NO positive material ID markings combined with no material certifications = scrap metal.

Regards, Wil Taylor

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[EdStainless]

Chem, tensile, and a micro will tell you everything that you need to know.
But my approach would be what could it be that would of value to me? Maybe Q&T 4340, or some special alloy. Then check hardness and magnetism to see if it looks right. If not then just scrap it.

There was a very good PE question based on material identification and sorting years ago.
There are a lot of tricks to use for this. There is even a mil spec that give a flow chart for material ID without lab tools for scrap sorting.

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[tbuelna]

As WKTaylor noted, for an application that requires any traceability, the material should not be used. Even if the material is something exotic, or the 30 lengths of bar have significant weight, it would be best to sell them as rems. And then purchase a new batch of material having the necessary documentation. Consider that you might need to perform a lab analysis on each of the 30 pieces of bar stock to ensure they all conform to the same standard.

 

[Guest102023]

I've waited a very long time to say this, but I disagree with metengr.
A portable alloy analyzer is for alloy differentiation or sorting but does not perform chemical analysis (although many inspection companies want you to believe that, and they (over)charge accordingly). PMI cannot read carbon, crucial in low alloy steels. It would only work if you had a known variety of different alloys in your basket but have lost traceability; i.e., match up CMTRs with bars.
There are portable spark testers (OES, optical emission spectroscopy) that are expensive to hire but could be cost-effective for a larger number of tests. The bonus is you get the answer on the spot (pun not intended). Otherwise take shavings or cut off wafers and ship to a lab. The same lab could do hardness testing and metallography on the same wafers.
Whatever, at a minimum, to identify the alloy grade you need to determine chemical composition and hardness. That would not be enough to satisfy the requirements of the applicable ASTM standard though. However you might be able to positively tie the results to a delinked CMTR.


"If you don't have time to do the job right the first time, when are you going to find time to repair it?"

 

[EdStainless]

I sort of fall between Brim and Metengr on this.
Do you have an idea of what alloy these are? Is there an alloy that you hope that they are?
Then use the simplest tests possible to see if that is what you are working with.
If it is not a steel then a portable XRF unit might work.
But if C is critical (steels) then OE is usually the easiest option.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

 

[98RedRANG]

This is why I travel around with an XRF or OES;hardness tester,and minipolisher. LOL

All comes down to cost of testing vs. cost/use of alloy (I don't see mentioned length or diameter). Depends what your final use is and or customer needs in terms of certification.I would not take shavings however, to easily contaminated to trust carbon- but as mentioned a saw cut slice from each will give your answer for a few hundred bucks per bar. I don't know location, but I would guess it would be 1-2k (?) to have someone come onsite for a whole a day to do every bar (chem/hardness). If that seems pricey then you have bars of counterweights.

XRF gun will quickly tell you if your dealing with alloy steel (or not) and with hardness, get in you in the ball park of what you have on hand-but find a knowledgeable person to do that testing- not just someone who knows how to push a button and read the output number.

If your really looking to save $ you can try find a very 'experienced' metallurgist and with a grinder and file he may be able to narrow done the type of alloy steel and rough carbon level, then you could choose to scrap or test.

 

[dik]

WKTaylor... we structural guys overdesign things so much, they would never get off the ground...

Dik

 

[KENAT]

"NOTE. For aerospace applications, NO positive material ID markings combined with no material certifications = scrap metal. "

Well, unless there's a war on and someone suggests you can tell the materials apart by the sound they make when tapped.

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