Ftyw for 6063 T4

[MacGruber22]

Have a job to sign and seal railing manufacturer shop drawings. They have been building these things the same way for years, but the county is becoming very involved in reviewing. Trying to prove that their design works.

Main structural elements (post, etc) are 6061-T6 but they like to use 6063-T4 for intermediate rails and pickets. My issue is that I can't seem to find the weld-affected yield stress from the Alum. Design Manual or from the internet. The unaffected Fy is published on the internet but is also not in the ADM.

6061-T6 = 35 ksi and 15 ksi respectfully (42% of unaffected). Would it be reasonably conservative to take 42% of the 6063-T4 --> .42*13 ksi = 5.5 ksi?

I am not an aluminium expert so take it easy on me...

-Mac

 

[metengr]

Use the base metal welded yield strength versus the actual weld metal. That would be the more conservative approach.

 

[WKTaylor]

MacGruber22...

Are these welds primarily Butt [tensile] or Fillet [shear] or ???

NOTE.
Aluminum Association WATP23 Welding Aluminum Theory and Practice may give You insight into welding design [typ joint values] with 6061-T4 and 6063-T4.


Regards, Wil Taylor

o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

 

[MacGruber22]

They are fillet welds. But, maybe I wasn't clear - I am concerned with the reduced member capacity due to incoming members welding near high stress areas.

I am definitely going to check the WATP23 - thanks for that reference, WK.

-Mac