Chemical Requirements of A615 Rebar

[BigH]

Ron / Rob / et.al.

Just wondering why ASTM A615 requires that chemical tests be run and reported for carbon, manganese, phosphorus and sulfur; yet the only requirement in the specification (Clause 6.1) is that sulfur is to be less than 0.06%. Any thoughts?

 

[SlideRuleEra]

BigH - The short answer for me is "I don't know", but here is a thread that may have some clues. See the two articles provided by kslee1000:
thread194-241126
From looking at the articles very quickly there are comparisons between A615 and rebar specs used in other countries - all, except A615, have detailed requirements for rebar chemistry.

I speculate that the way the published A615 document has evolved over the decades has resulted in the quirk that the chemistry has been addressed (or ignored) in an odd, inconsistent manner.

http://www.SlideRuleEra.net

http://www.VacuumTubeEra.net

 

[BigH]

SRE - thanks for refreshing for me the thread. In looking at the results I have, the sulfur is fine. In looking at A36, the Mn is to be between 0.6 and 0.9 and in our sample it is 1.1. Still, there are other structural steels, A53 for instance where Mn can be up to 1.2 and A706 (which is quoted in the Dubai article) allows up to 1.56 for Mn. I found a very good reference for steel, in general

http://www.workshop.egat.co.th/eng_info_system/eis_standard_metal/ScriptStandardMetal/HCWSS.pdf

; and a good article about bolts:

http://appliedbolting.com/pdf/usbolts.pdf

 

[Ron]

BigH...one other reason for the lack of chemistry in A615 is that most rebar in the US is produced from recycled steel from a variety of sources. As long as the physical properties are met, there is little attention paid to the metallurgy of rebar.

Almost all of the rebar in our area comes from electric arc furnaces, charged with the lowest grade of scrap metal you can find (crushed auto bodies with all the plastic and die-cast aluminum parts still on there, crushed washing machines/dryers, etc.)...the slag from the process is almost unusable (expansive, inconsistent properties).