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Titanium
Titanium, pronounced ty TAY nee uhm (chemical
symbol, Ti), is a lightweight, silver-gray metal. Its atomic number is 22,
and its atomic weight is 47.88. The density of titanium lies between that
of aluminum and stainless steel. It melts at 1667 C (10 C) and boils
at 3287 C.
Titanium resists seawater and sea-air corrosion or rust as well as
platinum and better than stainless steel. Many highly corrosive acids and
alkalies do not affect titanium. It is a ductile metal--that is, it can be
drawn into wire. It also has a higher strength-weight ratio than steel.
All these qualities make it a metal of great importance.
Physical Characteristics
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Atomic # - 22
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Atomic Wt. - 47.88 amu
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Elemental Symbol - Ti
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Melting Point = 1667 oC
Chemical
Properties
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Resist acid corrosion
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Ductile, easily shaped
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Stronger than steel
Uses
of Titanium
The first commercial use of titanium was as an oxide to substitute for white
lead in paint. Titanium dioxide, or titanium combined with oxygen, is
produced as a white pigment that has superior power to cover surfaces in
painting. Titanium dioxide is also used in the manufacture of floor
coverings, paper, plastics, porcelain enamels, rubber, and welding rods.
Barium titanate, a compound of barium and titanium, can be used in place of
crystals in television and radar sets, microphones, and phonographs. The gem
titania is made from crystals of titanium oxide. When cut and polished,
titania is more brilliant than the diamond, though not quite so hard.
Titanium tetrachloride, or titanium combined with chlorine, has been used
for smoke screens, and is the starting point for making the metal.
Titanium metal serves as an important alloying element. The armed forces use
large amounts of titanium in aircraft and jet engines, because it is strong
but light. It also withstands operating temperatures up to about 427 C
(800 F), which makes it useful in many types of machinery. Because of its
superior qualities, titanium has a number of potential uses, such as armor
plate for ships, steam-turbine blades, surgical instruments, and tools. The
transportation industry would use large amounts of titanium in buses,
railroad trains, trucks, and automobiles, if the price of titanium could be
lowered enough to compete with the price of stainless steel.
Location of Deposits
Titanium ranks as the ninth most
plentiful element. But the difficulty of processing the metal makes it
expensive. Titanium is never found in a pure state. It usually occurs in
ilmenite or rutile. But it may be found in titaniferous magnetite, titanite,
and iron (see ILMENITE).
The leading titanium-producing countries include Australia, Canada, China,
India, Malaysia, Norway, and South Africa. Russia and Ukraine also have
significant deposits. Florida, Idaho, New Jersey, New York, and Virginia are
the chief titanium-producing states. Quebec is the only Canadian province
that produces the metal.
Discovery and manufacture. Titanium was discovered by William
Gregor of England in 1791, and named by Martin Klaproth of Germany in 1795.
It was not until the 1930's, however, that a refining method adaptable to
large-scale production was worked out by William Kroll of Luxembourg. The
DuPont Company first produced the metal commercially in 1948. At the present
time, production remains low because of the difficulty and expense of
separating titanium from the ores with which it is found. The United States
manufactures most of the refined metal. Japan and the United Kingdom also
manufacture titanium. Research is being conducted to increase its supply and
lower its cost.
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