Case Hardening and Carbon Content 1

[metalman8357]

Hi all,

I recently sent out samples of a competitors product to determine their material by ICP-AES. I was assuming that it was most likely AISI 1018 to 1024, but I was surprised when the results came back showing AISI 1026-1029. When the samples were sent out, the test agency was never told that these parts were carburized, and it's possible that a part of the case could have been tested with the sample. These parts are 0.186" in diamter with an effective case depth of 0.004-0.009". Personally speaking, I think that this could have skewed the carbon content higher on the test results. Anyone agree, or is the sequestered carbon from carburizing too small to explain this difference?

 

[Metalguy]

I think you guess right. Tell the lab next time.

"You see, wire telegraph is like a very long cat. You pull his tail in New York and his head is meowing in Los Angeles. Do you understand this? Radio operates the same way: You send signals here, they receive them there. The only difference is there is no cat." A. Einstein

 

[arunmrao]

Your guess is right. An experienced lab, can definitely define the needs and accordingly draw the samples. However, this time reveal, that it is a case carburized steel grade.

_____________________________________
"It's better to die standing than live your whole life on the knees" by Peter Mayle in his book A Good Year

 

[TVP]

I concur with the others. Almost certainly 1018-1024 rather than 1025-1029.

 

[Maui]

Provided the geometry and size of the sample allow it, I would think that it would be a fairly simply exercise to grind 0.010" off of the surface and re-test. That should give you your answer.

Maui

http://www.EngineeringMetallurgy.com

 

[arunmrao]

Elementary Dr Maui!, is what Sherlock Holmes would have said. A star to you Maui, I never thought of it.

_____________________________________
"It's better to die standing than live your whole life on the knees" by Peter Mayle in his book A Good Year

 

[metalman8357]

Called the lab. Apparently they can run it at half mass by digesting the outside material with acid. We'll see what happens. Personally I like Maui's suggestion the most...