Titanium (Ti) is the 22nd element on the periodic table - meaning it has 22 protons in its atomic nucleus. Since its discovery two hundred years ago, it rested as a relatively unimportant metal until the twentieth-century realization that titanium was an exceptionally strong yet unusually lightweight material, useful in aircraft, spacecraft, and a variety of industrial activities.
- Chemical Properties -
As a metal, titanium is a firm, inflexible material which appears to be an off-white in its pure form. It is highly useful because of its unusually high melting and freezing temperature (over 3000 degrees Fahrenheit), and its weight (much lighter than steel of the same strength, and much stronger than aluminum of the same weight).
Although normally a stable element, isotopes of titanium do begin to give off radiation if they are exposed to other highly radioactive materials. Several intrinsically radioactive isotopes are known, but, because of their very short half-lives, these only exist when manufactured in nuclear reactors or in other laboratory experiments. In general, the stable isotopes of titanium are all non-toxic to humans.
- Where Titanium is Found -
Somewhat less than 1% of the total rock content of the Earth is believed to be made up of titanium. Titanium is normally never found in pure form in nature; instead, like many metals, it is found in compounds, formed through ionic bonds. It is most often found in various minerals, especially ilmenite and rutile.
For this reason, the majority of titanium producers actually mine these mineral deposits, and then separate titanium through chemical processes. Major producers currently include those countries generally known more broadly for rare mining activities, such as Australia (the largest producer in recent years), South Africa, and Canada. Within the United States, according to the U.S. Geological Survey, titanium production occurs in just three states: Nevada, Oregon and Utah.
Away from the Earth, titanium has been identified in free-floating objects within the solar system, such as meteors, as well as within the Sun itself. When the Apollo missions brought back moon rocks, moreover, they found that the Moon's surface contains a far higher proportion of titanium dioxide than the Earth's crust. This discrepancy relates to theories about how the Moon originally formed, as well as raising speculation about the future use of the moon as a titanium source for spacecraft construction.
- Applications and Uses -
In general, according to the USGS data, there are two key uses for titanium: Paint and aircraft. Paint uses titanium dioxide as an additive; because this does not require purification or separation of the titanium, this is both the cheapest and most frequent form of titanium which consumers encounter. Paint uses titanium dioxide because it does not rust - and also holds its colour when exposed to months or years of sunlight. Its white colour and chemical usefulness also means it has been used in trace amounts in such widely dispersed applications as papers and toothpaste.
The more expensive form, pure titanium, is produced for applications which require very strong but lightweight metal, such as airplanes and spacecraft. Although military applications tend to be the most sophisticated, for many years civilian jet aircraft have also incorporated titanium into their designs. For example, today's major Boeing and Airbus designs all make use of titanium. Various high-level consumer goods, including automobiles and sporting goods, may also advertise titanium content as a means of demonstrating their strength and resilience under pressure.