Test for Steel Composition

[mxracer17788]

What is the best test for determining the composition of an unknown steel? I have a sample that I am going to have sent out, and I'm wondering what the best/cheapest method is for determining the composition. Also, what is a good ballpark for how much a test like this will cost?

Thanks,
Jeff

 

[Maui]

You can expect to pay approximately $250 for this type of analysis as a minimum. Provided you have a large enough sample for testing, heavier elements can usually be determined by X-ray difraction. Carbon and sulfur are often measured separately by combustion analysis.

nother option is optical emission, but many labs won't certify the results using this technique. ICP-AES is typically when when the sample size is simply too small for X-ray or other standard methods.

Maui

http://www.EngineeringMetallurgy.com

 

[Maui]

And I really wish that my computer would actaully type all of the letters that I hit. The second sentence should have read, "Another option is optical emission, but many labs won't certify the results using this technique. ICP-AES is typically used when the sample size is simply too small for X-ray or other standard methods."

Maui

http://www.EngineeringMetallurgy.com

 

[mrfailure]

$130/sample is my data point for most steels.

 

[redpicker]

Am I the only one who is currious how X-ray diffraction is going to result in a chemical analysis?

In my experience, optical emission is the standard method for chemical analysis in steels. I believe nearly all of the steel mills these days use OES for their ladle analyses (at least, all of the ones I have visited) and is the basis of their chemical analysis certification.

And, like mrfailure states, I would expect anywhere $125-$150 per sample at most labs for low-alloy steels (8 to 12 elements). Uncommon elements and dissolved gasses would be more, mostly because most spectrometers are not set-up for them and alternate analyses must be done.

rp

 

[metengr]

I use a local met lab that probably is one of the best in the US for performing chemical analysis because I know of several excellent met labs that outsource their chemical analysis testing to them because of lower cost, turnaround and reporting accuracy. For carbon and low alloy steels, the analysis method is ASTM E 415 and the cost is $150 USD.

 

[Maui]

Redpicker, I meant X-ray fluorescence (XRF). Thank you for pointing out that error. Apparently I have been overcharged as well, based on the other replies.

I have yet to work for a steel manufacturer who certifies their chemical analyses using optical emission spectroscopy (and I have worked in several steel mills). Most do have OEs on site, but from what I have seen they do not certify heat chemistries using them. What manufacturers do this that you know of?


Maui

http://www.EngineeringMetallurgy.com

 

[mrfailure]

OES and ICP results are accurate. Outside labs can achieve A2LA certification, which should mean results obtained can be used for certs and accuracy and precision of results are constantly checked, both internally and through round robin testing.

 

[redpicker]

I did not mean any disrepect, Maui, I just curious how X-ray diffraction methods could be used for chemical analysis.

In the spirit of non-commercialism, I won't mention any speciifc names. I will say I've been in mills in Texas, Alabama, Indiana, Ohio, as well as France. I saw at least half of them using OES while I was there. I'll admit that I did not see them run chemistries at the other mills, but I'd assume they were using OES. Now, this is based on experience over the base 20-25 years

At the mill in France, they did mention that they were considering adding another OES on the melt-shop floor, but mentioned that it was decided not to, since "a man with two watches never knows what time it is".

rp

 

[TVP]

Maui,

I have audited ~ 10 steel mills in the North America, and also worked at one mini-mill earlier in my career. Certification for carbon and alloy steels is performed according to ASTM E415 (Atomic emission spectroscopy or OES) and E1019 (combustion for C, S, On, N). This is the standard for automotive and general industrial customers. It is possible that highly alloyed grades (stainless steels, tool steels, etc.) use other methods in addition to or in place of these standards, but that is outside my area of expertise.

 

[Maui]

TVP, we were primarily testing stainless steels, tool steels, and high speed steels. It's interestiong that optical emission appears to be a standard technique for analyzing lower alloyed grades, but does not appear to be used in the analysis of the more highly alloyed grades that I am familiar with.

After consulting my invoice for chemical analysis I noted that I was charged $250, but it was for analyzing [italic] two [/italic] test specimens, not one. I was charged $125/sample, which is right in line with the pricing that everyone else reported in this thread. I should have waited to post only after confirming what I was actually being charged for, but was in too much of a hurry to type a response. Making two mistakes in a single post is very unusual, and is quite disturbing to me. This tells me that I have been far too busy lately.

Maui

http://www.EngineeringMetallurgy.com