In article 2fl6e.25112$Vx1.1382@attbi_s01,
"mustanger" wrote:

Zinc Chromate or Zinc Oxide has been the choice of aircraft manufacturers
since the 40's for priming or coating aluminum for corrosion protection.

Norm
aka Mustanger
www.aeromuseum.org

Two-part epoxy primer over Alodine is the currently-preferred method --
especially when used with two-part polyurethane paints.