importance. Copper, zinc, lead, and a large number of
Tin
nonferrous alloys are required in the construction and
maintenance of naval ships. Some of the more popular
Tin is seldom used aboard ship in its pure state,
nonferrous metals a welder encounters are copper,
but it has many important uses as an alloying element.
Tin and lead are used together to make soft solders;
brass, zinc, bronze, lead, and aluminum.
tin and copper are used together to make bronze. Tin
The various welding processes now make it
possible to satisfactorily weld practically all
to corrosion.
nonferrous metals.
Brass
Copper
True brass is an alloy of copper and zinc.
Additional elements--aluminum, lead, tin, iron,
Copper is one of the most important nonferrous
manganese, or phosphorous--may be added to give
metals used in the construction of a ship. It is used in
the alloy specific properties. Rolled naval brass (also
the form of sheets, tubing, wires, and in copper alloys
known as Tobin bronze) is about 60 percent copper,
such as brass and bronze. It is used to give a protective
39 percent zinc, and 0.75 percent tin. This type of brass
coating to other metals, and to fabricate many special
is highly resistant to corrosion.
parts.
Brass sheets and strips are available in grades
The properties of copper make it extremely useful
known as soft, 1/4 hard, 1/2 hard, full hard, and spring.
for many applications. It is easy to work; it is ductile,
Hardness is imparted to the brass by the process of
malleable, tough, strong, resistant to wear, and
cold rolling. Most grades of brass can be made softer
machinable. Copper is highly resistant to saltwater
by annealing the metal at a temperature of 800 to
corrosion and is an excellent conductor of both heat
1200F.
Bronze
ZINC
A bronze made of 84 percent copper and 16
percent tin was the best metal available for tools,
Zinc is used as a protective coating (galvanizing)
weapons, and so on, before techniques were developed
on steel and iron. Zinc is also used in the form of zinc
for making steel. Many complex bronze alloys,
chloride for soldering fluxes and as an alloying
containing additional elements such as zinc, lead, iron,
element in some brass and bronze.
aluminum, silicon, and phosphorous are now
available. The name bronze is now applied to any
High-purity zinc, in the form of sheets, rods, or
copper-base alloy that looks like bronze; in many
special shapes, is used to protect hulls, hull fittings,
cases, there is no longer a real distinction to be made
and many types of machinery from the effects of
between bronze and brass.
galvanic action.
Aluminum and Aluminum Alloys
Lead
Aluminum and aluminum alloys are widely used
Lead is probably the heaviest metal that you will
because they are lightweight, easily worked, and
ever use on board ship. Lead weighs about 700 pounds
strong in relation to their weight. There are now so
per cubic foot, but in spite of its weight, it is soft and
many different types of aluminum alloys in use that a
malleable. Lead is commonly supplied in sheet form,
special numbering system has been adopted for these
rolled up on a rod. To use it, you merely unroll it and
alloys.
cut off as much as you need.
Because of its softness, lead is often used as a
IDENTIFICATION OF METALS
backing material for punching and hammering
operations. Sheet lead is used to line sinks and to
Material is used daily and, normally, there will be
protect bench tops that are exposed to acids. Lead is
some material left over. Quite often the means of
marking the material was cut off, or worn off, leaving
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