[AMCTony]

Does anyone know if 7075 can be welded to 6061 by TIG or MIG Process? If so, what kind of rod is recomended. We TIG 6061 often with 4043 rod. would a 5356 rod be more appropiate for this? Any help would be appreciated.

[steele]

Seven thousand series alloys are generally considered unweldable except w/ some extremely sophisticated techniques such as electron beam or Friction Stir Welding. I haven't any documentation handy but there is a hard 2000 series alloy that can be welded to 6061, 2041 maybe.

[greg b]

I thought 7 series alloy could not be welded to but im fairly shore the sprockets on our dirt bikes are 7075 for ware resistance and i have tig welded the holes that hold them to the hubs so we can re drill the pitch to suit other models.The rods i used were 5053,I guess the best idea is to weld a couple of sample pieces together and give them a nick break & bend test to suit your requirements good luck greg b

[davo727]

Hi, My friend at work is a master aircraft welder and he has told me that anything 7075 or 2024 alloy that is welded is very likely to crack either at the weld or right next to it. The weld may look ok but dont trust it or use it on anything critical as its not liable to last very long. If its for a bracket for a mailbox or something like that fine but not a racecar or airplane part. Dave

[miljnor]

not to mention any "T" rating is history if you weld on it.

And if you try to re-temper it the weld will definitely crack!

[Geof]

not to mention any "T" rating is history if you weld on it.

And if you try to re-temper it the weld will definitely crack!

How about if you anneal the material first, then weld, then re-anneal then re-temper. Athough I admit this sounds like an unrealistic sequence to go through I wonder if it would work.

[mxtras]

There are procedures that allow 7075 to be welded but I am not aware of the details. I am sure a detailed search with Google would turn up the answers.

I do know that I worked at a shop that welded an eloborate assembly together made exclusively of machined 7075 components. The welding had to be done preheated conditions and had to be kept extremely HOT (read - uncomfortable working conditions) during welding and then slowly cooled under controlled conditions. I am unsure if it was re-tempered. This PITA was discovered after the first fully machined parts had been welded into assembly #1 and it cracked like a cornered drug dealer. A specialist was called in to help get the project accomplished.

For all intents and purposes - don't weld it. Use commonly welded alloys and eliminate the fuss.

Scott

[miljnor]

How about if you anneal the material first, then weld, then re-anneal then re-temper. Athough I admit this sounds like an unrealistic sequence to go through I wonder if it would work.

Surely something to be studied, but best in the lab and not in the field.