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Corrosion between 316 stainless and aluminum

I'm having a corrosion issue with the interaction of a 316 stainless fastener with the threads of an aluminum rivnut insert in a wash-down environment. Changing to a stainless steel nut introduces galling issues that I would like to avoid. I was going to specify that the threads on each of the stainless fasteners be lubricated with a moly lubricant or spec a 304 stainless nut to mate with the 316 bolt so that the mating parts would have different hardnesses, but I thought there might be a better solution to the problem. As the application is a wash-down environment, I am always battling corrosion. Any suggestions as to fastener finish that might aid in my battle against corrosion?

Daniel Glenn
machine manufacturer - Fort Lauderdale, FL, USA
2004

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You are experiencing galvanic corrosion,using s/s and aluminum together (dissmiliar metals). What we would recommend is using all stainless. If galling is an issue - wax the mating part (nut).

Regards,

Beth Petersen
fasteners - Sanford, Florida, USA
2006