master alloy


Titanium is a chemical element with the symbol Ti and atomic number 22. It is a light, strong, lustrous, corrosion-resistant (including to sea water and chlorine) transition metal with a grayish color. Titanium can be alloyed with iron, aluminium, vanadium, molybdenum, among other elements, to produce strong lightweight alloys for aerospace (jet engines, missiles, and spacecraft), military, industrial process (chemicals and petro-chemicals, desalination plants, pulp, and paper), automotive, agri-food, medical prostheses, orthopaedic implants, dental endodontic instruments and files, dental implants, sporting goods, jewelry, mobile phones, and other applications.

Titanium was discovered in England by William Gregor in 1791 and named by Martin Heinrich Klaproth for the Titans of Greek mythology.

The element occurs within a number of mineral deposits, principally rutile and ilmenite, which are widely distributed in the Earth's crust and lithosphere, and it is found in almost all living things, rocks, water bodies, and soils. The metal is extracted from its principal mineral ores via the Kroll process or the Hunter process. Its most common compound, titanium dioxide, is used in the manufacture of white pigments. Other compounds include titanium tetrachloride (TiCl4) (used in smoke screens/skywriting and as a catalyst) and titanium trichloride (TiCl3) (used as a catalyst in the production of polypropylene).




Around the same time, Franz Joseph Muller also produced a similar substance, but could not identify it. The oxide was independently rediscovered in 1795 by German chemist Martin Heinrich Klaproth in rutile from Hungary. Klaproth found that it contained a new element and named it for the Titans of Greek mythology. After hearing about Gregor's earlier discovery, he obtained a sample of manaccanite and confirmed it contained titanium.

The processes required to extract titanium from its various ores are laborious and costly; it is not possible to reduce in the normal manner, by heating in the presence of carbon, because that produces titanium carbide. Pure metallic titanium (99.9%) was first prepared in 1910 by Matthew A. Hunter by heating TiCl4 with sodium in a steel bomb at 700–800 °C in the Hunter process. Titanium metal was not used outside the laboratory until 1946 when William Justin Kroll proved that it could be commercially produced by reducing titanium tetrachloride with magnesium in what came to be known as the Kroll process. Although research continues into more efficient and cheaper processes (e.g., FFC Cambridge), the Kroll process is still used for commercial production.


In the 1950s and 1960s the Soviet Union pioneered the use of titanium in military and submarine applications (Alfa Class and Mike Class) as part of programs related to the Cold War. Starting in the early 1950s, Titanium began to be used extensively for military aviation purposes, particularly in high-performance jets, starting with aircraft such as the F100 Super Sabre and Lockheed A-12.


Throughout the period of the Cold War, titanium was considered a Strategic Material by the U.S. government, and a large stockpile of titanium sponge was maintained by the Defense National Stockpile Center, which was finally depleted in 2005. Today, the world's largest producer, Russian-based VSMPO-Avisma, is estimated to account for about 29% of the world market share.




A metallic element, titanium is recognized for its high strength-to-weight ratio. It is a light, strong metal with low density that, when pure, is quite ductile (especially in an oxygen-free environment), lustrous, and metallic-white in color. The relatively high melting point (over 1,649 °C or 3,000 °F) makes it useful as a refractory metal.

Commercial (99.2% pure) grades of titanium have ultimate tensile strength of about 63,000 psi (434 MPa), equal to that of some steel alloys, but are 45% lighter. Titanium is 60% heavier than aluminium, but more than twice as strong as the most commonly used 6061-T6 aluminium alloy. Certain titanium alloys (e.g., Beta C) achieve tensile strengths of over 200,000 psi (1380 MPa). However, titanium loses strength when heated above 430 °C (800 °F).


The metal is a dimorphic allotrope with the hexagonal alpha form changing into the body-centered cubic (lattice) beta form at 882 °C (1,619 °F). The specific heat of the alpha form increases dramatically as it is heated to this transition temperature but then falls and remains fairly constant for the beta form regardless of temperature. Similar to zirconium and hafnium, an additional omega phase exists, which is thermodynamically stable at high pressures, but which may exist metastably at ambient pressures. This phase is usually hexagonal (ideal) or trigonal (distorted) and can be viewed as being due to a soft longitudinal acoustic phonon of the beta phase causing collapse of (111) planes of atoms.


The most noted chemical property of titanium is its excellent resistance to corrosion; it is almost as resistant as platinum, capable of withstanding attack by acids, moist chlorine gas, and by common salt solutions. Pure titanium is not soluble in water but is soluble in concentrated acids.

While the following pourbaix diagram shows that titanium is thermodynamically a very reactive metal, it is slow to react with water and air.

This metal forms a passive and protective oxide coating (leading to increased corrosion-resistance) when exposed to elevated temperatures in air, but at room temperatures it resists tarnishing. When it first forms, this protective layer is only 1–2 nm thick but continues to slowly grow; reaching a thickness of 25 nm in four years.

Titanium burns in air when heated to 1200 °C (2,200 °F) and in pure oxygen when heated to 610 °C (1,130 °F) or higher, forming titanium dioxide. It is also one of the few elements that burns in pure nitrogen gas (it burns at 800 °C or 1,472 °F and forms titanium nitride, which causes embrittlement). Titanium is resistant to dilute sulfuric and hydrochloric acid, along with chlorine gas, chloride solutions, and most organic acids. It is paramagnetic (weakly attracted to magnets) and has fairly low electrical and thermal conductivity.

Experiments have shown that natural titanium becomes radioactive after it is bombarded with deuterons, emitting mainly positrons and hard gamma rays. When it is red hot the metal combines with oxygen, and when it reaches 550 °C (1,022 °F) it combines with chlorine. It also reacts with the other halogens and absorbs hydrogen.


Producer Thousands of tons % of total
Australia 1291.0 30.6
South Africa 850.0 20.1
Canada 767.0 18.2
Norway 382.9 9.1
Ukraine 357.0 8.5
Other countries 573.1 13.6
Total world 4221.0 100.1
Source: 2003 production of titanium dioxide.
Due to rounding, values do not sum to 100%.


It is widely distributed and occurs primarily in the minerals anatase, brookite, ilmenite, perovskite, rutile, titanite (sphene), as well in many iron ores. Of these minerals, only rutile and ilmenite have any economic importance, yet even they are difficult to find in high concentrations. Significant titanium-bearing ilmenite deposits exist in western Australia, Canada, China, New Zealand, Norway, India and Ukraine. Large quantities of rutile are also mined in North America and South Africa and help contribute to the annual production of 90,000 tonnes of the metal and 4.3 million tonnes of titanium dioxide. Total known reserves of titanium are estimated to exceed 600 million tonnes.

Titanium is contained in meteorites and has been detected in the sun and in M-type stars; the coolest type of star with a surface temperature of 3,200 °C (5,792 °F). Rocks brought back from the moon during the Apollo 17 mission are composed of 12.1% TiO2. It is also found in coal ash, plants, and even the human body.

Production and fabrication





2TiFeO3 + 7Cl2 + 6C (900 °C) → 2TiCl4 + 2FeCl3 + 6CO
TiCl4 + 2Mg (1100 °C) → 2MgCl2 + Ti






Pigments, Additives and Coatings

About 95% of titanium ore extracted from the Earth is destined for refinement into titanium dioxide an intensely white permanent pigment used in paints, paper, toothpaste, and plastics. It is also used in cement, in gemstones, as an optical opacifier in paper, and a strengthening agent in graphite composite fishing rods and golf clubs. powder is chemically inert, resists fading in sunlight, and is very opaque: this allows it to impart a pure and brilliant white color to the brown or gray chemicals that form the majority of household plastics. In nature, this compound is found in the minerals anatase, brookite, and rutile. Paint made with titanium dioxide does well in severe temperatures, is somewhat self-cleaning, and stands up to marine environments. Pure titanium dioxide has a very high index of refraction and an optical dispersion higher than diamond.

Recently, it has been put to use in air purifiers (as a filter coating), or in film used to coat windows on buildings which when exposed to UV light (either solar or man-made) and moisture in the air produces reactive redox species like hydroxyl radicals that can purify the air or keep window surfaces clean.

Aerospace and marine

Due to their high tensile strength to density ratio, high corrosion resistance,and ability to withstand moderately high temperatures without creeping, titanium alloys are used in aircraft, armor plating, naval ships, spacecraft, and missiles. For these applications titanium alloyed with aluminium, vanadium, and other elements is used for a variety of components including critical structural parts, fire walls, landing gear, exhaust ducts (helicopters), and hydraulic systems. In fact, about two thirds of all titanium metal produced is used in aircraft engines and frames. The SR-71 "Blackbird" was one of the first aircraft to make extensive use of titanium within its structure, paving the way for its use in modern fighter and commercial aircraft. An estimated 59 metric tons (130,000 pounds) are used in the Boeing 777, 45 in the 747, 18 in the 737, 32 in the Airbus A340, 18 in the A330, and 12 in the A320. The A380 may use 146 metric tons, including about 26 tons in the engines. In engine applications, titanium is used for rotors, compressor blades, hydraulic system components, and nacelles. The titanium 6AL-4V alloy accounts for almost 50% of all alloys used in aircraft applications.


Titanium commercial aerospace requirements (including engine components [e.g., blades, discs, rings and engine cases] and airframe components [e.g., bulkheads, tail sections, landing gear, wing supports and fasteners]) for the manufacture of:

Boeing (including both the airframes and engines)

  • B787 – 295,000 pounds (133.8 tonne) of titanium
  • B777 – 130,000 pounds (59 tonne) of titanium
  • B747 – 100,000 pounds (45.4 tonne) of titanium
  • B737 – 40,000 pounds (18.1 tonne) of titanium

Airbus (including both the airframes and engines)

  • A380 – 320,000 pounds (145.1 tonne) of titanium
  • A350 – 165,000 pounds (74.8 tonne) of titanium (estimated minimal requirement)
  • A340 – 70,000 pounds (31.8 tonne) of titanium
  • A330 – 40,000 pounds (18.1 tonne) of titanium
  • A320 – 26,000 pounds (11.8 tonne) of titanium

Source: TIMET 2007 Form 10-K (converted from metric tons to pounds)



Consumer and architectural

Titanium metal is used in automotive applications, particularly in automobile or motorcycle racing, where weight reduction is critical while maintaining high strength and rigidity. The metal is generally too expensive to make it marketable to the general consumer market, other than high-end products, particularly for the racing/performance market. Late model Corvettes have been available with titanium exhausts, and racing bikes are frequently outfitted with titanium mufflers and titanium fastener kits (i.e., nuts and bolts), to reduce sprung weight while still being able to withstand the stresses of racing. Titanium alloy is used for the connecting rods in the engine of the 2006 and later Corvette Z06. Other automotive uses include piston rods and hardware (bolts, nuts, etc.). Very exotic performance vehicles often make greater use of the material, and custom factory (non-homologated) racing vehicles make extensive use of it.

The Parker Pen Company used titanium to form the T-1 fountain pen, later expanded to T-1 ball pens and rollerballs. The T-1 fountain pen was introduced in 1970 and the T-1 rollerball and ball pen in 1971. Production was stopped in 1972 due to the high cost of manufacturing titanium. Parker T-1's are prized for their collectibility by collectors.

Hammer heads made of titanium were introduced in 1999. Their light weight allows for a longer handle which increases the velocity of the head and results in more energy being delivered to the nail, all while decreasing arm fatigue. Titanium also decreases the shock transferred to the user because a titanium head generates about 3% recoil compared to a steel head that generates about 27%.

Titanium is used in many sporting goods: tennis rackets, golf clubs, lacrosse stick shafts; cricket, hockey, lacrosse, and football helmet grills; and bicycle frames and components. Titanium alloys are also used in spectacle frames. This results in a rather expensive, but highly durable and long lasting frame which is light in weight and causes no skin allergies. Many backpackers use titanium equipment, including cookware, eating utensils, lanterns, and tent stakes. Though slightly more expensive than traditional steel or aluminium alternatives, these titanium products can be significantly lighter without compromising strength. Titanium is also favored for use by farriers, since it is lighter and more durable than steel when formed into horseshoes. Titanium horseshoes can be found in horse racing, and are used by many Amish horse owners, who rely entirely on horse-drawn carriages for transportation.

Because of its durability, titanium has become more popular for designer jewelry in recent years, whereas until recently the metal was too difficult to work into the intricate shapes with the precision necessary for fine jewelry. Today, titanium rings — including engagement rings and wedding bands — are one of the fastest growing segments of the titanium jewelry market, in part due to the ability of the metal to be grooved, inlaid, and carved without losing strength. Some titanium jewelry also incorporates diamonds or other gemstones, typically in close settings such as bezels, flush, or tension designs. Its inertness again makes it a good choice for those with allergies or those who will be wearing the jewelry in environments such as swimming pools. Titanium is used in watchmaking for the production of watch cases. Watchmakers appreciate titanium for its durability, light weight, dent- and corrosion- resistance. Titanium watches are often coated with a protective material to make the surface more scratch-resistant.

Titanium has occasionally been used in architectural applications: the 120 foot (40 m) memorial to Yuri Gagarin, the first man to travel in space, in Moscow, is made of titanium for the metal's attractive color and association with rocketry. The Guggenheim Museum Bilbao and the Cerritos Millennium Library were the first buildings in Europe and North America, respectively, to be sheathed in titanium panels. Other construction uses of titanium sheathing include the Frederic C. Hamilton Building in (Denver, Colorado) and the 350 foot (107 m) Monument to the Conquerors of Space in Moscow.

Due to its superior strength and light weight when compared to other metals traditionally used in firearms (steel, stainless steel, and aluminium), and advances in metal-working techniques, the use of titanium has become more widespread in the manufacture of firearms. Primary uses include pistol frames and revolver cylinders.




Its inertness and ability to be attractively colored makes it a popular metal for use in body piercing. Titanium may be anodized to produce various colors. A number of artists work with titanium to produce artworks such as sculptures, decorative objects, and furniture.


The +4 oxidation state dominates in titanium chemistry, but compounds in the +3 oxidation state are also common. Because of this high oxidation state, many titanium compounds have a high degree of covalent bonding.


Titanium nitride (TiN) is often used to coat cutting tools, such as drill bits. It also finds use as a gold-coloured decorative finish, and as a barrier metal in semiconductor fabrication.

Titanium tetrachloride (titanium(IV) chloride, TiCl4, sometimes called "Tickle") is a colourless liquid which is used as an intermediate in the manufacture of titanium dioxide for paint. It is widely used in organic chemistry as a Lewis acid, for example in the Mukaiyama aldol condensation. Titanium also forms a lower chloride, titanium(III) chloride (TiCl3), which is used as a reducing agent.






Titanium is non-toxic even in large doses and does not play any natural role inside the human body. An estimated 0.8 milligrams of titanium is ingested by humans each day but most passes through without being absorbed. It does, however, have a tendency to bio-accumulate in tissues that contain silica. An unknown mechanism in plants may use titanium to stimulate the production of carbohydrates and encourage growth. This may explain why most plants contain about 1 part per million (ppm) of titanium, food plants have about 2 ppm, and horsetail and nettle contain up to 80 ppm.

As a powder or in the form of metal shavings, titanium metal poses a significant fire hazard and, when heated in air, an explosion hazard. Water and carbon dioxide-based methods to extinguish fires are ineffective on burning titanium; Class D dry powder fire fighting agents must be used instead.

Even bulk titanium metal is susceptible to fire, when it is heated to its melting point. A number of titanium fires occur during breaking down devices containing titanium parts with cutting torches.

When used in the production or handling of chlorine, care must be taken to use titanium only in locations where it will not be exposed to dry chlorine gas which can result in a titanium/chlorine fire. Care must be taken even when titanium is used in wet chlorine due to possible unexpected drying brought about by extreme weather conditions.

Titanium can catch fire when a fresh, non-oxidized surface gets in contact with liquid oxygen. Such surfaces can appear when the oxidized surface is struck with a hard object, or when a mechanical strain causes the emergence of a crack. This poses the possible limitation for its use in liquid oxygen systems, such as those found in the aerospace industry.

Salts of titanium are often considered to be relatively harmless, but its chlorine compounds, such as TiCl2, TiCl3, and TiCl4, have presented several unusual hazards. The dichloride takes the form of pyrophoric black crystals, and the tetrachloride is a volatile fuming liquid. All of titanium's chlorides are corrosive.

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