Dissimilar Metal Corrosion Potential Chart

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OverEasy
Admiral
Posts: 2012
Joined: Mon Sep 28, 2020 11:16 am
Sailboat: MacGregor 26X
Location: NH & SC

Dissimilar Metal Corrosion Potential Chart

Post by OverEasy »

Hi All!

Here’s a handy ‘Quick Reference Chart’to help with your repair and modification projects relating to the aspect of
Dissimilar Metals Galvanic Corrosion Potentials.
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As you can see from the chart there is a high potential of corrosion ( especially in the presence of water or salt water which act as an electrolyte ) between Aluminum alloys and Stainless Steel alloys.

This can be mitigated by incorporation of a barrier layer between the contact surfaces.
Generally a nitrile rubber or plastic washer can be utilized to beneficial effect as can paints.
A favorite of mine is to apply nail polish to the Stainless Steel fasteners (clean & degreased) contact surfaces when using them on Aluminum Alloy components. It’s easy to store in your tool box, dries relatively quickly and not only comes in color to allow you to see where you have treated but also in clear for those situations where you want a clean & neat appearance.

Nitrile, plastic and nylon washers are generally available in the specialty fastener aisles of places like Lowes, HomeDepot, Menards and Ace
Hardware Stores (and others) as well as from various on-line retailers.

Hope this helps!

Best Regards,
Over Easy 😎😎🐩🐈
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