TIG welding inconel stainless?

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I had my first experience with TIG welding inconel stainless today (308 stainless plate to T22 steel, inconel filler).  Just curious what you guys thought of the characteristics of inconel.  I noticed a discernably more sluggish puddle, and a definitive difference in color over the 309L I'm used to.  Any other opinions out there?
Reply:Been a while but yeah, it runs like jello. Most of what I did got PWHT but occasionally I'd have to do a small touch-up repair and if it was a problem area it was permissable to very lightly "butter" with nickel filler first. Very lightly...the extra nickel really smooths it out and wets it in.Anything worth doing is worth doing RIGHT
Reply:Do you know what Inconel alloy you are using, 600 or 625?Off hand I don't know the metallurgy of the 308/T22/Inconel mix, so I wonder if this is this an established/tested welding procedure, or just an experiment.I worked on automotive products using both inconel 600 and 625, fusion welded to mild steel.  These products were 100% helium leak tested, and we had severe problems with liquation cracking and leaks with the 625 alloy due to a low melting point niobium compound in the 625 weld.
Reply:It was 625, and was just an experiment for one of my undergrad courses.  No back purge, so a solar flux was used.
Reply:Pretty good read guys, keep it up. I use this stuff for spear tips. Should I use 600 series if I decide to weld on it??And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:Welding Inconel -or- stainless (steel)???   Inconel alloys are "super alloys", not "stainless steel alloys".  Inconel alloys are mostly nickel, next element is usually chromium, and then some other elements including some iron, all depending on the specific alloy.So no surprise that 'buttering' the other metal with some high-nickel rod/filler helps smooth the weld of Inconel to the dissimilar metal.But Supe wasn't welding Inconel.  He played with TIG welding some 308 and used Inconel 625 wire as the filler?  The chromium percentage of the 308 and the 625 filler are a close match (~20-21%), but the other elements are all over the place in the mismatch.  Mostly a flip-flop in the iron vs nickel percentages.  So, what was the question again?
Reply:Originally Posted by MoonRiseWelding Inconel -or- stainless (steel)???   Inconel alloys are "super alloys", not "stainless steel alloys".  Inconel alloys are mostly nickel, next element is usually chromium, and then some other elements including some iron, all depending on the specific alloy.So no surprise that 'buttering' the other metal with some high-nickel rod/filler helps smooth the weld of Inconel to the dissimilar metal.But Supe wasn't welding Inconel.  He played with TIG welding some 308 and used Inconel 625 wire as the filler?  The chromium percentage of the 308 and the 625 filler are a close match (~20-21%), but the other elements are all over the place in the mismatch.  Mostly a flip-flop in the iron vs nickel percentages.  So, what was the question again?
Reply:Originally Posted by SupeI had my first experience with TIG welding inconel stainless today (308 stainless plate to T22 steel, inconel filler).  Just curious what you guys thought of the characteristics of inconel.  I noticed a discernably more sluggish puddle, and a definitive difference in color over the 309L I'm used to.  Any other opinions out there?
Reply:Type 347 is a "stablized" stainless steel with titanium additions to help prevent "carbide precipitation", the formation of chromium carbides which would reduce corrosion resistance, by instead preferentially forming titianium carbides.