duplex stainless

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does anyone have experience working with Duplex stainless steel, specifically alloy 2250 or 255 "super" duplex?  structural applications, plate thicknesses 1/4" to 1/2". would appreciate your feedback.Last edited by AnneD; 12-05-2010 at 07:26 PM.Reason: added "plate"
Reply:wow, I thought you guys would be all over this one! should I move the question to a different forum?
Reply:I would suggest posting it in the metallugry or welding technical sections.There are several people who post there who are stainless experts.There is plenty of literature in print.  If you want the basics you could start by going to www.suppliersonline.com.I have a good book by Stoody called Stainless Welding Engineering.  It has a whole chapter devoted to Duplex alloys.Duplex is not so hard to weld but there are some special requirements related to control of pitting corrosion.  One important aspect is control of ferrite numbers when selecting the welding filler materials - but that is usually well controlled by a good welding spec if a spec is used.I am currently working with WPS and PQR documents where duplex is used but I can not go into details since proprietary information is involved.Actually, I made a mistake with this post.  I forgot where I was and thought I was at the AWS.ORG site.  I think you would get more responses if you post over there in the metallurgy section.Last edited by obewan; 12-05-2010 at 07:54 PM.
Reply:Thank you sir.
Reply:Originally Posted by AnneDwow, I thought you guys would be all over this one! should I move the question to a different forum?
Reply:Actually, I should have told you to search the forum at AWS.  They get a  little frustrated when people post up topics which have already been discussed.  I checked and there have been many discussions regarding duplex.  The people there like it best when people post very specific questions about very specific problems with lots of details.  But, if you just want to read about duplex stainless welding, here is the link to the forum:http://www.aws.org/cgi-bin/mwf/forum...ime&order=desc
Reply:I'm sure a web search will yield a ton of technical info.  As I recall, duplex SS is designed to be a specific mixture of austenitic and ferritic structure, to give good corrosion resistance, higher strength than the 300 series (austenitic), and good ductility.  The welding process can affect factors such as heat input, cooling rate, and nitrogen pickup which causes the austenite/ferrite ratio in the weld to vary from what is ideal.  The welding procedure should be qualified by demonstrating tthat the required mix of austenite and ferritecan be produced.
Reply:[QUOTE=SR20steve;445263]You waited a whole hour to post this? I guess you think that you can snap your fingers and get answers.No, of course not. Why can't you take it as a compliment? You're all experienced metalworkers.
Reply:Personal opinion, or preference, would have been fine, as in "love it," "difficult to work with," "use it in such and such industry," whatever. Like obewan said, the technical information can be found on technical sites. I just wondered what experience anyone has had. Shop talk.