Need Help with A-36 Semikilled or Killed 2

[tgregg]

I work for a Tank Fabrication Company and we are trying to prove that some 3/8" thk. A-36 is semikilled or killed. The material is foreign and doesn't dipict semikilled or killed on the MTR. An inspector is giving us some grief about it and I know there is some way to prove or disprove this but can't find it anywhere. Any ideas? Somebody said that the Silicon and or Aluminum content might be the key but we have no legitimate sources to back it up. Thanks

 

[arunmrao]

Killed steel always contain silicon and aluminium additions,which are absent in semi killed. For a source backup you need to refer to this classic volume on steel making,which will give you the necessary details. Hope it helps.



The Making, Shaping and Treating of Steel (Steel Making and Refining) (Book and CD-ROM) (Hardcover)
by United States Steel Co. (Corporate Author), American Society for Metals (Editor), Richard J. Fruehan (Editor)

 

[CoryPad]

From ASM Handbook Volume 1 Properties and Selection: Irons, Steels, and High Performance Alloys:

Killed steels are fully deoxidized during their manufacture; deoxidation can be accomplished by additions of silicon, aluminum, or both, or by vacuum treatment of the molten steel. Because it is the least costly of these methods, silicon deoxidation is frequently used. For silicon-killed steels, a range of 0.15 to 0.30% Si is often specified, providing the manufacturer with adequate flexibility to compensate for variations in the steelmaking process and ensuring a steel acceptable for most applications. Aluminum-killed or vacuum-deoxidized steels require no silicon; a requirement for minimum silicon content in such steel is unnecessary. A maximum permissible silicon content is appropriate for all killed plain carbon steels; a minimum silicon content implies a restriction that the steel must be silicon killed.

Regards,

Cory

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[deanc]

You may consider taking a sample for grain size.

http://www.metallography.com/bboard/messages/2002/10644.html

http://www.principalmetals.com/glossary/gdoc.htm

This is common when a mill runs light on Al.

 

[stanweld]

Semikilled steels were typically made to have a Silicon content from 0.01% to 0.10%.