Can AL 7075 be welded?

[Anvils]

I have a 7075 forging that has a small damaged spot that I would like to weld and remachine.
This is a non critical / non stressed part. ( not an aircraft part). Anyone have experience repairing this stuff? I checked with my welding supplier today and they said it was not weldable but some on line information said it is. If it can be welded what filler rod (TIG) should be used?
Thanks, Norm

[KINGWELD]

Short answer is NO.
7075 has 5.6% zinc which does nothing for a weld but screw it up.
Welding WILL destroy the heat treatment.
Since this is a forging, I'm going to say leave it alone. It has been forged for strength.
Best to error on the side of safety.

[Willy]

Is it possible to perhaps drill or mill out the damaged spot and then press a plug of 7075 into the hole and refinish?
It's just for cosmetic reasons, no?

[gnm109]

The link below is from the Lincoln Company's website and concerns common mistakes in aluminum weldments. As mentioned above by Kingweld, they say that 7075 is definitely not weldable, at least for structural applications. That leaves open the question of what other use there might be for it and why you might want to use it.

Here's a brief excerpt.

"With the few exceptions noted below, the designer should assume that the 7XXX alloys are non-weldable. The most common of these alloys is 7075, which should never be welded for structural applications. In addition, these alloys often suffer from poor corrosion performance in many environments."


http://www.lincolnelectric.com/knowl...comistakes.asp

[gnm109]

Is it possible to perhaps drill or mill out the damaged spot and then press a plug of 7075 into the hole and refinish?
It's just for cosmetic reasons, no?

If it's merely cosmetic, JB weld followed with some silver paint. Don't laugh.

The issue of zinc as mentioned above is reason enough not to go near it with your TIG torch.