ALUMINUM/STAINLESS STEEL INTERFACE
ALUMINUM/STAINLESS STEEL INTERFACE
(OP)
We need to secure a flange made from 6061 Aluminum angle with 1/2 dia Grade 316 stainless steel bolts. The flange offers a flat surface exposed to weather with a 30 year service life in a mildly corrosive industrial environment. The nut and washer face into the weather.
Can anyone advise us what we can anticipate in terms of corrosion/deterioration for this connection.
Can anyone advise us what we can anticipate in terms of corrosion/deterioration for this connection.





RE: ALUMINUM/STAINLESS STEEL INTERFACE
Another way to prevent galvanic corrosion here is to electrically isolate the SS bolts from the Al flange with suitable bushings (Teflon is a common material).
You could have the Al flange anodized or coated with some other, rugged coating and keep it whole during the bolting.
RE: ALUMINUM/STAINLESS STEEL INTERFACE
RE: ALUMINUM/STAINLESS STEEL INTERFACE
RE: ALUMINUM/STAINLESS STEEL INTERFACE
Need some advice. We are specifying a racking system for PV modules (sheltered outdoor application). The basic construction is aluminum blocks (~1"x2"x2") bolted to a rail. The question is whether to use a HD galvanized rail or a stainless rail. The environment is rural but might have elevated SO2 levels because this is on the roof of a winery. The galvanized rail obviously will not last as long as the stainless (though the Zinc Coating Life Predictor indicates adequate life) but I am concerned about the galvanic couple. Also the aluminum block has two large (3/8") 18-8 bolts through it, the manufacturer claims this will not be a problem.
Thanks for the help!
RE: ALUMINUM/STAINLESS STEEL INTERFACE
See reply in the other thread.