Welding duplex to Nitronic?

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Can anyone tell me the best welding rod to use to join 2304 duplex to nitronic 33?
Reply:Ok, I need a few more bits of information, how much welding over all? use of end product? why do you need to weld duplex and nitronic 33? please give as much information as you can.
Reply:Approximately 120' of weld. Fillet weld. Customer supplied material. Not pressure retaining.
Reply:pre heat isn't required nitronic 33, common welding techniques can be used.  Filler metal selection should be of similar chemistry for maximum strength and resistance to intergranular attack. I believe you already knew that. The problem comes with the Duplex, you need to control the hydrogen levels from welding, this is most easily obtained with TIG. Ideally you will need to use a stainless rod, with low hydrogen content. I would suggest that you not weld the two together, but I will see if I can find more information for you over the next few hours.
Reply:Thank you for the help
Reply:Nitronic 33 use rod E240 or solid metal core wire ER240, or any of the following, nitronic 35w, 312 will match base metal strength and corrosion resistance.Duplex 2304-Filler metal should be a balanced ferrite/ austenite type, duplex is a good alternative to 316L SS price wise, but not to be used where duplex will reach and maintain a temp 300 C. Some of the problem with citing one weld filler metal is that most duplex 2304 are not the same, they are manufactured all over the world and with out th knowledge about the specifics of the 2304. Now duplex should NEVER be welded with out filler metal, use of pure argon and TIG is the most successful. Duplex welding consumables are suitable for joining duplex to austenitic stainless steel or carbon steel; they can also be used for corrosion resistant overlays.  Nickel based welding consumables can be used but the weld strength will not be as good as the parent metal, particularly on super duplex. This is the most I am willing to give via the internet, I would highly suggest that you contact a welding engineer in your country, or perhaps your company has a W.E. that you can go to.
Reply:I forgot to add interpass temp for duplex should not exceed 150 degree's C
Reply:Thank you mm. You have been most helpful. I have enough to be going on with now.