MIL-STD-889C - Department of Defense, Standard Practice, Dissimilar Metals
"Scope: This standard defines and classifies dissimilar metals and establishes requirements for protecting coupled dissimilar metals against corrosion with attention directed to the anodic member of the couple."
Taken from the ASSIST website. ASSIST is the official source for specifications and standards used by the United States Department of Defense. ASSIST provides free access to Defense Standardization Program technical documents that have been cleared for public release.
In our opinion, the ASSIST website can be difficult and time-consuming to navigate. So:
(Scroll to page 7 for the start of the galvanic series chart.)