`Navy Ship Aluminum-Steel Transition Joints - Galvanic Corrosion`

Three-ply explosive-bonded transition joint allowing fusion welding of an aluminum superstructure to a steel hull. Galvanic corrosion in seawater is the persistent problem; the Sheffield case (§4.p2) is the proposed consequence.

Another application is to make plates that bond aluminum and steel together. [Tom shows a three-ply transition joint.] These are transition joints where you slammed aluminum against steel in an explosive bonding operation, then cut it up. This is what the Navy does for all the superstructures on their ships. The hull of the ship is made of steel because it needs to be inexpensive and have good capability against people shooting at it. The superstructure — the top of the ship — needs to be lightweight, or the ship will tip over in a storm. So they have a steel base plate and put one of these transition joints in. This one happens to be a three-ply: carbon steel to aluminum, with one of these transition plugs.