protecting aluminum in outdoor environments
protecting aluminum in outdoor environments
(OP)
We are making an all aluminum antenna to be used in the California desert. It will remain outside for 10-20 years. We would like aluminum that has good conductivity for low loss and we need to paint it white.
Questions:
1) I read alloy 1100 is the best conductor, do you suggest using this or another aluminum alloy (3000, 6061)?
2) What paint is suggested to protect from the environment. We also have to paint a plastic front cover (the plastic has not been chosen, Tefzel maybe).
Thanks,
kch
Questions:
1) I read alloy 1100 is the best conductor, do you suggest using this or another aluminum alloy (3000, 6061)?
2) What paint is suggested to protect from the environment. We also have to paint a plastic front cover (the plastic has not been chosen, Tefzel maybe).
Thanks,
kch





RE: protecting aluminum in outdoor environments
Regards,
Cory
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
RE: protecting aluminum in outdoor environments
RE: protecting aluminum in outdoor environments
RE: protecting aluminum in outdoor environments
RE: protecting aluminum in outdoor environments
We are making a 4 foot box shape with an open top.
We need only the outside surface painted. The inside must remain unpainted.
The type aluminum will be chosen by Mechanical consultants unless I specify a type, or some options. They are doing wind load analysis and may choose their own for maximum strength and lightest weight.
Regarding conductivity: what is the percentage referenced to? copper or some other standard?
Thanks for the 6xxx reference.
Side-question:
We need to make good electrical contact with the sheet aluminum and our RF connectors and cables. Is there a reference to search regarding, conductivity and aluminum coatings (i.e. is anodizing or iriditing or powder coating better for electrical contact between our connectors&cables and our chosen aluminum?)
Thanks,
sorry if I've strayed to another forum with the side-Q.
kch
RE: protecting aluminum in outdoor environments
RE: protecting aluminum in outdoor environments
RE: protecting aluminum in outdoor environments
TTFN
RE: protecting aluminum in outdoor environments
There will be a few good dust storms per year hitting our antenna, so powder coat with epoxy sounds recommended.
btrueblood "The so-called marine aluminums (50xx series) with Al and Mg, are pretty robust." I would think that the title "marine aluminums" would be pretty resistant to corrosion. Do you know if the conductivity at the 50xx series surface is good, and whether it oxidizes alot to protect itself in the marine environment (that would be bad, I can see our antenna going bad after a few years). I had heard that standard Aluminum at sea doesn't do too well.
Sounds like good progress,
Thanks for the inputs, addition inputs welcome,
kch
RE: protecting aluminum in outdoor environments
The biggest "problem" with the 5xxx series is that they are not hardenable, so you are stuck with a yield strength of about 13 ksi (for 5052) to 23 ksi (alloy 5456), unless you get the product in a strain-hardened (work hardened) condition. But, I've routinely formed 90-deg. bends in 1/8" sheet 5052 at half-hard (30 ksi yield) condition. And it welds beautifully.
RE: protecting aluminum in outdoor environments
Regards,
Cory
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
RE: protecting aluminum in outdoor environments