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Does anyone know anything about Aluminum 7075? I know that climbing hardwear is generally made out of the stuff, but how hard is it to weld? is it better to cast it? How much does the stuff cost? where can you get it? ect.......

sjarelkwint wrote:Can you give me the EN AW number?

7075 is the EN AW number. My understanding is that T6 is the commonly used temper, but I'm no metallurgist. Aluminum 6061 is also used, for instance for some cam lobes.

If you weld it you will have to heat treat it maintain the design strength, and heat treating aluminum is a pretty controlled, scientific process.

I do not remember the exact yield stress numbers associated with the different material grades and specific heat numbers, but as a point in case, I knew a guy that built a recumbent out of 6061 T6 tube, welded the joints but did not reheat treat (making it T0). The joints broke when riding over a bump. T0 on 6061 is 20-25% the strength of T6.

7075 has the same approximate heat treatment relationship. This might be useful:

http://archive.metalformingmagazine.com ... 6/Alum.pdf

7000 series and 2000 series Al are typically not weldable.

You would definitely need to heat treat it. For 7075, temper O has only 33 percent of the yield strength of T62.

I hope you're not gonna DIY any safety gear...

sjarelkwint wrote:

Buz Groshong wrote:You would definitely need to heat treat it. For 7075, temper O has only 33 percent of the yield strength of T62.

Don't know enough technical english for this discussion

I know we used it in my former company for welding some parts in trucks for the belgian army... 1 out of 50 employers was able to weld it

That should be "employees."

Oh, and I couldn't weld my way out of a paper bag, but I do have access to lots of material standards that provide info on strength and composition of materials.

benjydaniel wrote:Does anyone know anything about Aluminum 7075? I know that climbing hardwear is generally made out of the stuff, but how hard is it to weld? is it better to cast it? How much does the stuff cost? where can you get it? ect.......

7075, one of the strongest of the aircraft alum alloys.

Not weldable by conventional methods and not recommended to be welded

not generally used for casting either

Usually either machined from billet or forged. All the good beaners are forged, cams are machined.

one of the most expensive of the common aluminum alloys

www.mcmastercarr.com sells it in a few shapes

http://www.mcmaster.com/#aluminum-alloy-7075/=8iczed