Naval brass is designed to be exceptionally strong and to resist corrosion. It is an alloy that is made of 39.2 percent zinc, 0.75 percent tin, and the remaining 60 percent copper. Naval brass has been used for many years in the construction of marine vessels. It is suitable for use in saltwater or freshwater.
Due to its durability and its ability to resist corrosion, naval brass is often a main component of propeller shafts. It is also used for decorative fittings and other marine hardware. Naval brass is used in the different structural parts of marine vessels, including heat exchanger tubes and valve stems.
One aspect that gives naval brass its strength is the addition of the 0.75 percent tin. Brass that is used in non-naval applications does not include tin; instead, it is an alloy made of zinc and copper. Adding tin to the mixture makes naval brass resistant to dezincification.
Dezincification is a process where one of the components of an alloy is removed via corrosion. This is a problem that was first recognized in the brass tubes that ships had for condensers around the year 1920. Since 1920, many different alloys have been created to prevent the de-alloying of metal, one of which has been naval brass.
While naval brass is primarily used on marine hardware, it is also used in other applications. Some bushings are designed with naval brass because of its higher tensile strength and resistance to wear.