Residual Elements in Stainless Steels 4

[hnaziri]

Happy New Year.

I was stumped by a customer asking how it is determined what residual elements should be reported in a heat analysis. Is there any documentation to show, i.e., how ASTM, AISI or AMS standards agreed to require certain elements and not others?

 

[EdStainless]

The requirements in ASTM are very clear. You must report all specified elements and anything that is deliberatly added. There are some funny little catches and exceptions that you can read in A480.
A grade cannot contain an unspecifed element to the extent that it then also qualifies as another grade where that element has a specified minimum concentration....
One exception in tubing in the addition of Nitrogen. This does not disqualify the use of material, 304LN can be certified as 304L also.
It is also good to read A751 on this subject.

= = = = = = = = = = = = = = = = = = = =
Corrosion, every where, all the time.
Manage it or it will manage you.

http://www.trent-tube.com/contact/Tech_Assist.cfm

 

[mcguire]

You should also realize that, while EdStainless is right as usual, many elements are known to be in a heat as "tramp" elements and are analyzed at the producing mill and not reported. Elements such as boron and titanium are deliberately added quite routinely, while inescapable elements like Pb, Sn, Cu, Co, Mo are always there for good or evil whether reported or not.

Michael McGuire

http://stainlesssteelforengineers.blogspot.com/

 

[hnaziri]

Thank you both for your inputs.