exotic metals HELP PLEASE

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I NEED AS MUCH INFO AS POSSIBLE ABOUT TIG WELDING THESE METALS,,,,,,,,,,,,,,,,,,,,,,,inconel and hastelloy    NICKEL BASED ALLOYS                                            WHAT TUNGSTON,WHAT SHEILDING GAS,AMPERAGES,WHAT POLARITY,    ANY INFO WILL HELP   THANKS
Reply:You might start by explaining your situation so responders don't need to ask you a thousand questions, or write an online book instead!Also, a few Caps. to highlight specific words is OK but all caps is just harder to read. Let me start by saying that Nickle alloys adsorb impurities like lead, even from traces of grease, so everything needs to be exceedingly clean.Last edited by Oldiron2; 06-26-2010 at 12:20 AM.
Reply:thanks,,,,,,,,i just read nickel based alloys are poor heat conductors,needs to be clean like you said, use just enough amps to get the puddle moving,,,,and go with it.,..i also read they recommend using a large cup to get pleanty of shelding gas ot the puddle will get SLUGGISH......   i will be taking a interview for a place that makes power plant turrbines and things of that nature.they have alot of dealing with nickel based alloys....i have been looking for a more serious welding job and i have a interview monday it sound like....any advice on tig welding with nickel based alloys will help huge........thank you all for any tips!!!
Reply:You know in tig class, we hardly even looked at the textbook. It was all labtime.Basically, nickel resists corrosion and adds strength. Cobalt comes into play with high temperature service. The problems in welding lie with porosity and cracking. Proper base material/ filler material consideration is needed. Weld design is crucial, groove angles should be wider because these metals don't "wet" readily. Use full-pen joints whenever possible. Use minimum restraint when welding, (allow it to "move"). Absolute cleanliness of filler and base metals fits the bill. Never use unidentified filler, they all look alike. Root side of welds requires shielding. Hi freq for arc starts and 1-2% thoriated, anything over 1/8" thick requires the addition of helium to the mix. Here's one I never woulda thunk, 95% Ar/ 5% hydrogen will leave a cleaner, brighter weld crown.Hope that helps and ain't too much of a book. City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:Have a play with google, Haynes have a lot info freely available for example...http://www.haynesintl.com/weldinginformation.htmhttp://www.haynesintl.com/pdf/h2010.pdfhttp://www.twi.co.uk/content/jk22.htmlPuddle will be sluggish, poor gas coverage and/or dawdling will just make it worse and more 'scummy' with oxides. Argon/hydrogen mixes help as the H provides a reducing atmosphere to scavenge oxygen. At the end of the day if given a weld test on exotics there'll almost certainly be a WPS in placeLast edited by hotrodder; 06-26-2010 at 02:06 AM.
Reply:Sounds like the OP needs to take a trip to the library.  You know, the place where information is stored in books, like in the old days before the internet.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:DC -, 2% THORIATED TUNGSTEN, ARGON GAS, GAS LENSE, PULSED TIG.Yes this metal is a poor condutor of heat. This metal also releases impurities like invar stellite and inco.Yes your gonna have a sluggish puddle, constantly brush and weld small sections unless you are mig welding this metal. Oh, dont forget to where a 3m particle mask for the smoke you WILL get sick and fever. Good luck
Reply:Ditto thermalfusioneng.Your amp settings will be very close to 18-8 type stainless, penetration will be shallow. The filler will stand up and not follow the heat very well.Pulse will help flow the edges down, but don't puddle around at all.Also Nickle and Cobalt Chrome materials are very prone to crater cracking and there will be a specific procedure there to deal with that..Good LuckMatt