I’m looking for a non-corroding and magnetic washer for use in a salt water environment. Specifically, we plan to weld this washer onto a 316 stainless basket so that it can be attached to a magnet. Currently we are using 302 stainless baskets, which are magnetic enough to attach to the magnet directly. However, we are concerned about long-term corrosion.

For seawater, I would recommend Super Duplex 2507 washers. The Super Duplex 2507 material should will have about 65% iron about 5% less than the 302 Stainless. I’m not sure if it will be magnetic enough for your application but it certainly will work well in seawater. Duplex washers are often used in salt water environments for their high resistance to pitting, erosion and crevice corrosion, as well stress corrosion cracking (SCC) in chloride environments.