Alclad aluminum aerospace sheet — roll-bond and continuous-cast clad processes

Seventy-year history of roll-bonding 1100 aluminum onto 2014/2024 cores to prevent galvanic micro-cells from copper precipitates. Recent (~mid-2000s) commercial development by a Spokane WA inventor of continuous direct-chill casting that fuses two alloys at a single fusion line, dropping clad-sheet costs and opening kitchen-appliance and brazed-radiator markets.

Aluminum in general has very good corrosion resistance as pure aluminum. That picture of the Aloha Airlines — the outside skin is a clad aluminum. For sixty, seventy years we've been making roll-bonded aluminum. You take a heat-treatable aluminum plate, typically 2024 — in fact when I had that FAA manual, the old MIL-Handbook-5, I opened it up and it was 2014 Alclad. They call it aluminum-clad aluminum.