Ampco Metal 21 is an aluminum bronze having high hardness, good compressive strength and resistance to wear and corrosion. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and compressive strength as well as fracture toughness. It also includes information on corrosion resistance as well as casting, machining, and joining. Filing Code: Cu-93. Producer or source: Ampco Metal Inc..