What is most cost efficient at resisting corrosion on steel surfaces?

I'm planning to sell solar water heaters that could end up near salt water and have run into a problem. Some people love stainless steel, thinking it is the ultimate in corrosion resistance, without realizing there are many grades of it, and not all of them are good at resisting corrosion.

I'm thinking I should have a PVDF powder coating that is heat treated, but this is my amateur opinion. I'd love to hear what experts think. The main point is how do you make a reasonably strong and rust resistant external metal tank (the internal is SUS 304 2B) and a stand that doesn't cost an arm and a leg.

I should add that this area regularly has Hurricanes, so they want it strong as well. That may restrict what can be used for the stand.

Thanks for your input!

Hi, Ken. Everyone wants to be cost efficient, and still we have thousands of different materials of construction and thousands of different surface coatings. It's not an easy job suggesting the best material and the best surface finish.

But aluminum is strong, light, relatively inexpensive, and (when properly coated) corrosion resistant. So as an alternative to your PVDF powder coated steel, I'd look into powder coated aluminum. If aesthetics aren't a principal concern, and it must be steel, you might consider galvanized steel and omit the powder coating.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey