Not logged inAmerican Welding Society Forum
Forum AWS Website Help Search Login
Up Topic American Welding Society Services / Certifications / Stainless Steel Testing
- - By Leily Date 02-21-2006 00:56
I am working with my boss to set up Welding procedures and pre-qualified testing on 304 stainless steel. We know that we need a chemical to test the weld, however we can not find it anywhere in the books we have.

Does anyone know the chemical we need or where we might find the information. It is referenced in the literature we've read, but can't find the specific chemical name.

Your help is greatly appreciated.
Parent - - By MBSims (****) Date 02-21-2006 03:26
If you are talking about chemicals for macroetching stainless steel welds, then Aqua Regia etchant would be used for stainless steel welds. It must be mixed from 1 part nitric acid (HNO3) with 3 parts hydrochloric acid (HCl) by volume. This must be done by a person experienced in mixing acids under a fume hood. If no one in your company is experienced and/or the proper safety equipment is not available, then it would be advisable to have a local metallurgical testing company perform the work.

Having said that, I thought a "prequalified" welding procedure was one that required no testing. What code are you working to?
Parent - - By jon20013 (*****) Date 02-21-2006 12:42
I was going to make exactly the same comment Marty, regarding stainless and "prequalified." I'm wondering if the person asking is perhaps confusing terms, maybe they have a "Standard Welding Procedure Specification" (SWPS)?
Parent - - By - Date 02-21-2006 22:00
AWS D1.6 (Structural Welding Code - Stainless Steel) makes provision for prequalified welding procedures, much like D1.1.
Mankenberg
Parent - By jon20013 (*****) Date 02-22-2006 12:44
It sure does, while I own a D1.6 and once worked that committee I guess I didn't realize they had included the prequalifieds... good stuff, thanks for that info!
Parent - - By G.S.Crisi (****) Date 02-21-2006 21:03
As a chemical engineer, I don't understand why do you need to make a chemical test on the weld.
As far as I know, welds are tested only by means of physical tests: bending, tensile, impact, metallurgical structure etc.
You can determine the approximate chemical composition of the welded metal knowing the chemical composition of the base metal and of the electrode (or rod, if you're using TIG) and the dilution, which is a function of the welding method you're using (SMAW, MIG, TIG, FCAW).
Giovanni S. Crisi
Sao Paulo - Brazil
Parent - - By jon20013 (*****) Date 02-21-2006 21:35
Giovanni; it sounds to me as though they wish perhaps to etch the weld.
Parent - - By G.S.Crisi (****) Date 02-22-2006 22:10
Leily,
would you be kind enough to clear up jon's as well as my doubt?
Giovanni S. Crisi
Parent - By vonash (**) Date 02-23-2006 23:15
Hmm, me too.
Up Topic American Welding Society Services / Certifications / Stainless Steel Testing

Powered by mwForum 2.29.2 © 1999-2013 Markus Wichitill