Titanium is a transition metal known for its very high strength and low density. As a chemical element, it has the symbol Ti and the atomic number 22. It has a shiny color similar to the one of silver and excellent resistance to corrosion, including exposure to chlorine or aqua regia. Despite the unique properties of titanium, it was rarely used in metal alloys until the 1950s. Today, it has many industrial applications, since it is one of the most durable metals and it is inexpensive to produce. It is as strong as steel but with a 45% lighter weight. While it is 60% heavier than aluminium, it is twice as durable. William Gregor was the first to discover titanium in 1791, in the British province of Cornwall. Martin Heinrich Klaproth later gave it the current name, inspired by mythical Greek creatures. Titanium is very common in the Earth's crust and all waters, soils, rocks or even living creatures include it. It is found in many mineral deposits and the best mineral ores with a content of titanium are rutile and ilmenite, both quite common. Kroll and Hunter processes are the main methods of titanium extraction from such ores. Titanium dioxide is probably the most used compound of this metal, especially in the production of white pigments and as a photo catalyst. Titanium tetrachloride (TiCl4) is also a catalyst but is also found in smoke screens. The production of polypropylene needs another titanium catalyst, the compound titanium trichloride (TiCl3). Titanium is usable in alloys with many other elements, especially iron, aluminium, molybdenum or vanadium. These alloys are very strong while having a light weight at the same time, so they are widely used in the production of spacecraft, jet engines, missiles and other aerospace and military applications. It is also widely used in industry, in particular in desalination plants, the production of pulp and paper, as well as chemical and petrochemical compounds. It has numerous other applications, including dental and endodontic instruments and files, dental implants, medical prostheses, orthopedic implants, sporting goods, jewellery, mobile phones and automotive parts. Titanium alloys are the material of choice in any scenario where a light and strong metal is needed. The most common use cases are the production of structural elements, bicycle frames, as well as parts for planes or vehicles. Titanium needles and pins don't react with the human flesh or bones, so they are excellent for medical applications. The metal is also used to manufacture body piercing and surgical instruments. This metal is very resistant to sea water corrosion, especially when protected by a coating of platinum. As a result, it is heavily used in water desalinization plants and some parts of ships that are always exposed to the action of water, for example rigging elements or propellers. Many military applications are also based on titanium. Alloys made from this element are found in great quantities in the armour plates of almost all vehicles, airplanes, helicopters, submarines or missiles. The Soviet Union built submarines entirely from titanium during the Cold War, since these were able to submerge deeper due to the higher resistance to pressure, while having a higher top speed. Even if titanium is not considered to be a precious metal, it is widely used to produce jewellery. It is quite inert and can be colored in various attractive tones. Titanium jewelry doesn�t cause adverse reactions even to people who are extremely sensitive to other metals. Titanium is used in large amounts in the production of alloys but also has many other commercial uses. It is needed in the manufacture of gemstones because titanium dioxide (TiO2) gives previous stones like rubies and star sapphires the reflection that resembles a star. The dioxide is also useful as painkiller and provides protection from the effects of solar radiation, so it is a common ingredient of sunscreen. Letters written in the sky by planes, a technique known as skywriting, are made using titanium tetrachloride (TiCl4).
Titanium is one of the biocompatible metals, since the body doesn't reject it and there are no toxic effects. As a result, it is widely used in medical applications, for example the production of joint replacements and hip balls, as well as other surgical implements. Titanium dental implants can last more than 20 years for example. The typical medical alloys have a 4% aluminium content or contain both aluminium and vanadium. A very useful property of titanium is the ability to integrate with bones easily. This makes it extremely effective in dental implants with a very long life, as well as many other types of medical or surgical implants. This metal has a natural elasticity that is very similar to the one of human bones, so it is perfect for repairing them. The bone and the implant end up evenly sharing the pressure on the skeleton, so the bone degrades very slowly. The risk of periprosthetic bone fractures, which usually appear where implants are connected to the bones, is greatly reduced. However, the bones located near titanium implants can degrade in time, since they have to support a reduced load due to the superior durability of the metallic alloy. Titanium implants can be examined using magnetic resonance imaging without any risks, since this is not a ferromagnetic metal, which is very convenient and allows implants to be used for a long time. Before titanium is implanted in the body, a plasma arc is used to generate high temperatures. This eliminates the atoms at the surface and exposes a fresh layer, which oxidizes instantly. Many items that must have a low weight but high durability are made of titanium. These include crutches and wheelchairs but also the tools that needed for modern image-guided surgery techniques. Nanoparticles of titanium dioxide are also found in electronic items, as well as some cosmetic and pharmaceutical products. While titanium is often used in metallic form, most of it is actually transformed into oxide. The oxide is a very common white pigment, included in various items from plastics to toothpaste. Titanium oxide is also used to improve the strength of golf clubs or fishing rods. Desalination plants produce drinking water from salty sea water. The heat exchangers that are a main element in their operation must resist sea water corrosion, so they are made from titanium. Since this metal is totally inert and doesn't react at all with other elements, it is ideal for body piercing. Another important advantage in this role is the fact that it can be colored quite cheaply. The metal is also very well suited for dental implants and increasingly used for this purpose. MRI machines can be used safely by people with such implants. Other body implants, such as artificial joints or hip balls, can last for 20 years or more if made from titanium. Since it is light and very strong, the metal is also used in the production of firearms. Some laptops have titanium bodies, for the same reasons. It is also found as a construction material, when durability is needed. Sports items such as bicycle frames, helmet grills, tennis rackets or cricket helmets are often made from it. Titanium has become extremely popular for the manufacture of jewellery lately, and it is so fashionable now that it has actually started replacing silver and gold in this role. It is perfect for the production of bands or rings because it is very strong and resists denting. A type of soft artificial gemstones can also be manufactured from titanium. The metal and its alloys are widely used in the medical industry. Titanium eyeglass frames can be very light and resilient. The same features make the metal a great choice for other items like bone plates and screws, pacemakers, artificial replacements for hip and knee joints, crutches, dental implants and some types of surgical instruments. Space vehicles and aircraft are usually made from titanium due to the very high durability, as well as some of their engine parts. The aerospace industry was actually one of the first to rely on this metal. The SR-71 "Blackbird" spy plane manufactured in the 1960s is one of the earliest titanium craft and it proved the exceptional qualities of the metal. Since then, titanium has been a material of choice for many types of planes, especially military ones. Today, even commercial planes like Airbus or Boeing models use titanium extensively in their engines and frames. Sporting gear is often made from titanium whenever low weight and high strength are desired. The most common items include hockey sticks, helmet grills, bicycle frames, golf clubs, tennis rackets, cricket bats and many others. The metal is extensively used in the construction of racing cars and motorcycles, since the reduced weight is very important. Cooking items made from titanium are becoming increasingly popular. Besides cookware, many quality travel products designed for backpackers are made from titanium due to its low weight, for example lanterns or tents. Titanium art objects are also gaining significant traction lately. Titanium is opaque, which makes it suitable for some industrial uses. The most important is soldering, especially techniques based on waves and ultrasounds. When in contract with moist air, titanium tetrachloride generates dense fumes. As a result, it is used for smoke screens and sky writing, when released from airplanes.