welding inconel

[Little Ed]

Anyone out there have any thoughts on welding Inconel to copper? My thinking is that inconel welds a lot like stainless, so that would be TIG DC straight. But I think that pure copper would be AC. Anybody Know for sure? I am going to try running them together with AC, but it will probably take a lot of heat to get the copper to puddle. Maybe put some kind of a heat sink on the inconel side to keep it from melting way ahead of the copper, sort of a copper, inconel, heat sink sandwich. But then that would require a lot of heat into the entire assembly. This assembly has to conduct electric current, which heats up the inconel, which performs a welding function on plastic. It has to maintain 500 degrees C. Would any of the silver solders hold up to that heat? Thanks for reading.

 

[Welding man]

Welded some copper many years ago with Tig, but I think we had to use helium as shielding gas, argon wouldn't work. I would think Sil Fos silver solder would hold up at that temp easily. Used to use it on copper steam lines.

 

[Anonymous-0]

I also think silver solder would work. Handy & Harman are the silver solder and brazing specialists. Maybe check on their website for more info. Dave

 

[Bud in FLA]

I never tried welding iconel to copper but I did learn that inconel flows, copper doesn"t!
Stick inconel on boiler tubes looked like mercury running down the pipe. It was an oil fired biler - couldn"t get the base metal clean enough for inconel to stick.

Copper does NOT flow and you can"t "push" it while you"re welding. It just "lumps" where it contacts the base metal. Copper transfers heat REAL well, too! Plan on heating just about the entire piece of copper to get it to weld. Plan on HOT day in the office.....

 

[Oldmax]

Inconel is a Nickel/Crome Alloy you might have a problem welding it to copper. If you had Incloy might be possible.Used to work at INCO as an inspector.

 

[Bob - MI]

I would be surprised if you can get good joining. Inconel has a high nickle composition to resist high temperatures. It also has high chromium levels. It is also prone to poor flow characteristics and oxidation if not properly handled. Chrome oxides are brittle and can't be eliminated once formed.

In the casting world, it's important to know what alloy you are dealing with. IN-625 is a formulation that can be melted in air. It is important to keep a flood of argon gas over the melt to reduce oxidation. This would suggest that you will be using lots of cover gas.

Most other Inconel alloys can't be melted in anything other than full vaccuum without suffering contamination. Vaccuum melt alloys are usually welded in an argon glove box.