Tungum is an aluminum-nickel-silicon brass (83% Cu, 1.2% Ni, 1% Al, 1% Si) that is not well known these days but is finding new applications in copper aquaculture. Invented in the UK in the 1930s, it performs extremely well in seawater and marine atmospheres. The alloy is mainly used in commercial diving and offshore applications due to its resistance to salt water corrosion. Example applications include marine hydraulic control, instrument lines, decompression chamber living and sleeping sections for divers. Tungum resists both pitting and crevice corrosion in marine environments/atmospheres. The alloy offers excellent service-life, even at intermittent duty in the corrosive "splash" zone. It is defined under BP Specification GP 36-15-1 for mitigating/preventing external corrosion in topside small-bore tubing for operating pressures up to 5000psi.
References
- Copper Alloys for Marine Environments, Carol Powell and Peter Webster, Publication 206, Second Revision, , CDA UK, .