Baltimore Gas and Electric under-deposit corrosion

Brief reference — Admiralty brass condenser tubes failed by under-deposit attack thirty or forty years ago at BG&E.

Yellow brass — that's what people used to use. Number three in thermal conductivity. Admiralty brass and aluminum brass are alloyed a little bit, we lose a little, but the aluminum brass has this good aluminum oxide skin, so it has good erosion resistance. That sample passed around, that prototype propeller — manganese aluminum bronze is what the Navy uses for ship propellers. Admiralty brass is what they were using thirty or forty years ago at Baltimore Gas and Electric, where they had the under-deposit attack I was talking about. You can use nickel — kind of pricey, but it's still got pretty good corrosion resistance. Carbon steel, we all know, rusts. The Navy likes to use cupro-nickel — 70/30s, or the Monels, which are 30/70 cupro-nickel. Now you're really biting the dust. You can use stainless steel, but it tends to pit. Titanium is better than stainless and has fantastic corrosion resistance. If you have to go to really high temperatures, well beyond water, you can use some of the nickel-based alloys. There's a whole host of materials. If you're talking about condenser tubes or boiler tubes, these are the types of materials you use. If you're talking nuclear reactors, boiling water reactors typically use stainless steels; pressurized water reactors, we're getting into the Inconels. It has to do with the operating temperatures and conditions.