AMPCOLOY 521 is a cast copper-nickel alloy with excellent resistance to many highly active corrosives, particularly saline waters and sulfuric and phosphoric acids. It has high strength and good ductility and can be welded readily. Its many applications include valves, pump bodies, steam fittings and plumbing parts. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as casting, heat treating, machining, joining, and surface treatment. Filing Code: Cu-408. Producer or source: Ampco Metal Inc..