plating, anodizing, & finishing Q&As since 1989
Corrosion Between a Black Anodized Aluminum Part and a Yellow Zinc Plated Part
September 24, 2008
Is there any potential for corrosion building up when a black anodized aluminum plate is attached with steel bolts and nuts to a yellow zinc plated steel surface?Dieter Eberhard PMP
Project Manager - Arlington, Texas, USA
September 26, 2008
Hi, Dieter. What finish is on the steel nuts and bolts? Presumably zinc plating and clear chromating?
Zinc plating and aluminum anodizing are somewhat close in electrochemical potential -- but everything is relative. For an aircraft it's a no-go; for interior use it sounds fine; for exterior use the zinc plating probably won't last that long anyway.
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey